Astronomy Picture of the Day |
APOD: 2023 November 19 – Space Station, Solar Prominences, Sun
Explanation:
That's no sunspot.
It's the
International Space Station (ISS)
caught passing in front of the Sun.
Sunspots, individually, have a dark central
umbra, a lighter surrounding
penumbra, and
no Dragon capsules attached.
By contrast, the ISS is a complex and multi-spired mechanism,
one of the largest and most
complicated spacecraft ever created by
humanity.
Also, sunspots circle the
Sun,
whereas the ISS orbits the
Earth.
Transiting the Sun is not very unusual for the
ISS, which orbits the Earth about every 90 minutes,
but getting one's location, timing and equipment just right for a
great image is rare.
The featured picture combined three images all taken in 2021 from the
same location and at nearly the same time.
One image -- overexposed -- captured the faint
prominences seen across the top of the Sun,
a second image -- underexposed -- captured the complex texture of the
Sun's chromosphere,
while the third image -- the hardest to get -- captured the space station as it
shot across
the Sun in a fraction of a second.
Close inspection of the space station's
silhouette even reveals a docked
Dragon Crew capsule.
APOD: 2023 January 7 - Space Stations in Low Earth Orbit
Explanation:
On January 3, two space stations
already illuminated by sunlight in low Earth orbit
crossed this dark predawn sky.
Moving west to east (left to right) across the composited
timelapse image
China's Tiangong Space Station
traced the upper trail captured
more than an hour before the local sunrise.
Seen against a starry background
Tiangong passes just below
the inverted Big Dipper asterism of Ursa Major
near the peak of its bright arc,
and above north pole star Polaris.
But less than five minutes before, the
International Space Station
had traced its own sunlit streak across the dark sky.
Its trail begins
just above the W-shape outlined by the bright
stars of Cassiopeia near the northern horizon.
The dramatic foreground spans an abandoned mine at Achada do Gamo
in southeastern Portugal.
APOD: 2022 December 18 - The 25 Brightest Stars in the Night Sky
Explanation:
Do you know the names of some of the brightest stars?
It's likely that you do, even though some bright
stars
have names so old they date back to near the beginning of
written language.
Many world cultures have
their own names for the
brightest stars, and it is
culturally and historically important to remember them.
In the interest of clear global communication, however, the
International Astronomical Union (IAU) has begun to designate
standardized star names.
Featured here in true color are the 25 brightest stars in the night sky,
currently as seen by
humans, coupled with their
IAU-recognized names.
Some star names have
interesting meanings, including
Sirius ("the scorcher" in
Latin),
Vega ("falling" in
Arabic),
and Antares ("rival to Mars" in
Greek).
You are likely even familiar with the name of at least one star
too dim to make this list:
Polaris.
APOD: 2022 November 12 - Eclipse in the City
Explanation:
A darker Moon sets over Manhattan in this night skyscape.
The 16 frame composite was assembled from consecutive
exposures recorded during the
November 8 total lunar eclipse.
In the timelapse sequence stars leave short trails above the
urban skyline,
while the Moon remains immersed
in Earth's shadow.
But the International Space Station was just emerging
from the shadow
into the sunlit portion of its low Earth orbit.
As seen from
New York City, the visible streak of this ISS flyover starts
near a star in Taurus and tracks right to left,
through the belt of Orion and over Sirius, alpha star of Canis Major.
Gaps along the bright trail of the fast moving orbital outpost
(and an aircraft flying closer to the horizon)
mark the time between individual exposures in the sequence.
The trail of bright planet Mars is at the top of the frame.
Pleiades
star cluster trails are high over the eclipsed Moon and
Empire State Building.
APOD: 2022 July 9 - Saturn and ISS
Explanation:
Soaring high in skies around planet Earth, bright planet
Saturn was a star of
June's morning planet parade.
But very briefly on June 24 it posed with a bright object in
low Earth orbit, the International Space Station.
On that date from a school parking lot in
Temecula, California the ringed-planet and
International Space Station
were both caught in this single
high-speed video frame.
Though Saturn was shining at +0.5 stellar magnitude
the space station was an even brighter -3
on the magnitude scale.
That difference in brightness is faithfully represented
in the video capture frame.
In the challenging image, the orbiting ISS was at a range of 602 kilometers.
Saturn was about 1.4 billion kilometers from the
school parking lot.
APOD: 2022 May 20 - A View from Earth's Shadow
Explanation:
This serene sand and skyscape finds the
Dune of Pilat
on the coast
of France still in Earth's shadow during the early morning hours of May 16.
Extending into space, the
planet's dark umbral shadow covered the Moon
on that date.
From that location the
total phase of a lunar eclipse
had begun before moonset.
Still in sunlight though, the
International Space Station
crossed from the western horizon
and
Earth's largest artificial moon traced the bright flat arc
through the sky over 400 km above.
Simply constructed, the well-planned panoramic scene was captured
over a 5 minutes in a series of consecutive images.
APOD: 2022 April 11 - A Space Station Crosses a Busy Sun
Explanation:
Typically, the International Space Station is visible only at night.
Slowly drifting across the night sky as it orbits the Earth, the
International Space Station (ISS) can be seen as a
bright spot several times a year from many locations.
The ISS
is then visible only just after sunset or just before
sunrise because it shines by reflected sunlight --
once the ISS enters the Earth's shadow, it will drop out of sight.
The only occasion when the
ISS is visible during the day is when it
passes right in front of the Sun.
Then, it passes so quickly that only cameras
taking short exposures can visually freeze the
ISS's silhouette onto the background
Sun.
The featured picture did exactly that --
it is actually a series of images taken earlier this month from
Beijing,
China with perfect timing.
This image series was later combined with separate images
taken at nearly the same time but highlighting the
texture and activity on the busy
Sun.
The solar activity included numerous gaseous
prominences seen around the edge, highlighted in red,
filaments seen against the Sun's face, and a dark
sunspot.
APOD: 2022 March 24 - Arp 78: Peculiar Galaxy in Aries
Explanation:
Peculiar
spiral galaxy Arp 78 is found within the boundaries of the head strong
constellation Aries.
Some 100 million light-years
beyond the
stars and nebulae of our Milky Way galaxy,
the island universe is over 100,000 light-years across.
Also known as NGC 772, it sports a prominent, outer spiral arm in
this detailed cosmic portrait
from the large
Gemini North telescope near the
summit of Maunakea, Hawaii, planet Earth.
Tracking along sweeping dust lanes and
lined with young blue star
clusters, Arp 78's spiral arm is likely pumped-up by galactic-scale
gravitational tidal interactions
The close companion galaxy responsible is NGC 770, located off the
upper right of this frame.
But more distant background galaxies are clearly visible in the
cosmic
field of view.
APOD: 2021 December 6 - Space Station Silhouette on the Moon
Explanation:
What's that unusual spot on the Moon?
It's the
International Space Station.
Using precise timing, the
Earth-orbiting space platform
was photographed in front of a partially lit
gibbous Moon last month.
The featured composite, taken from
Payson,
Arizona,
USA last month,
was intricately composed by combining, in part, many 1/2000-second images from
a video of the ISS crossing
the Moon.
A close inspection of this unusually
crisp ISS silhouette will reveal the outlines of
numerous solar panels and trusses.
The bright
crater Tycho is visible on the upper left,
as well as comparatively rough,
light colored terrain known as
highlands, and relatively smooth, dark colored areas known as
maria.
On-line
tools can tell you when the
International Space Station will be visible from your area.
APOD: 2021 October 12 - Fireball over Lake Louise
Explanation:
What makes a meteor a fireball?
First of all, everyone agrees that a
fireball is an exceptionally bright meteor.
Past that, the
International Astronomical Union
defines a fireball as a meteor brighter than
apparent magnitude -4,
which corresponds (roughly) to being brighter than any planet --
as well as bright enough to cast a human-noticeable shadow.
Pictured, an astrophotographer taking a long-duration sky image
captured by accident the brightest
meteor he had ever seen.
Clearly a fireball,
the disintegrating space-rock created a trail so bright it
turned night into day for about two seconds earlier this month.
The fireball
has been artificially dimmed in the featured image to bring up foreground
Lake Louise in
Alberta,
Canada.
Although
fireballs are rare,
many people have been lucky enough to see them.
If you see a fireball, you can
report it.
If more than one person recorded an image, the
fireball might be
traceable back to the
Solar System body from which it was
ejected.
APOD: 2021 October 10 - Full Moon Silhouettes
Explanation:
Have you ever watched the Moon rise?
The slow rise of a nearly full moon over a clear horizon can be an impressive sight.
One impressive moonrise was imaged in early 2013 over
Mount Victoria
Lookout in
Wellington,
New Zealand.
With detailed planning, an
industrious astrophotographer
placed a camera about two kilometers away and pointed it across the lookout to where
the Moon
would surely soon be making its nightly debut.
The
featured single shot sequence is unedited and
shown in real time -- it is not a time lapse.
People on
Mount Victoria Lookout
can be seen in silhouette
themselves admiring the dawn of Earth's largest satellite.
Seeing a moonrise yourself is not difficult:
it happens every day, although only half the time at night.
Each day the
Moon rises about
fifty minutes later
than the previous day, with a full moon
always rising at sunset.
This Saturday, October 16, is
International Observe the Moon Night,
where you observe a
first-quarter Moon along with
other lunar enthusiasts.
APOD: 2021 September 27 - Unwrapped: Five Decade Old Lunar Selfie
Explanation:
Here is one of the most famous pictures from the Moon -- but digitally reversed.
Apollo 11 landed on the moon in 1969 and soon thereafter many pictures were taken, including an
iconic picture of
Buzz Aldrin taken by
Neil Armstrong.
The original image captured not only the
magnificent desolation of an
unfamiliar world,
but Armstrong himself reflected in Aldrin's curved visor.
Enter modern digital technology.
In the
featured image, the spherical distortion from Aldrin's helmet has been reversed.
The result is the
famous picture -- but now featuring Armstrong himself
from Aldrin's perspective.
Even so, since Armstrong took the picture, the image is effectively a five-decade old lunar selfie.
The original visor reflection is shown on the left, while
Earth hangs in the lunar sky on the upper right.
A foil-wrapped leg of the
Eagle lander is prominently visible.
Preparations to return humans to
the Moon in the next few years include the
Artemis program, an
international collaboration led by NASA.
APOD: 2021 June 26 - Pixels in the Sun
Explanation:
These two panels, composed of video frames made
with a safe solar telescope and
hydrogen alpha filter,
show remarkably sharp details on
the solar disk
and giant prominences along the Sun's edge on June 6 (top) and June 18.
Taken from Beijing, China, they also show a transit of the
International Space Station and China's new
Tiangong Space Station
in silhouette against the bright Sun.
The
International Space Station
is near center in the bottom panel,
crossing the solar disk left of bright active region AR2833 and below
a large looping solar filament.
China's space station is below solar active region AR2827 and
right of center in the top panel,
seen as a smaller, combined "+" and "-" shape.
The pictures of the
transiting orbital outposts
were taken with the same equipment and at the same pixel scale,
with the International Space Station some 492 kilometers away.
China's space station was over 400 kilometers
from the camera.
APOD: 2021 April 29 - Apollo 17: The Crescent Earth
Explanation:
Our fair planet
sports a curved, sunlit crescent
against the black backdrop of space in this stunning photograph.
From the unfamiliar perspective,
the Earth is small
and, like a
telescopic image of a distant planet,
the entire horizon is completely within the field of view.
Enjoyed by
crews on board
the International Space Station,
only much closer views of the planet are possible from low Earth orbit.
Orbiting the planet once every 90 minutes, a spectacle of clouds, oceans,
and continents
scrolls beneath them
with the partial arc of the planet's edge in the distance.
But this digitally restored image
presents a view so far
only achieved by 24 humans,
Apollo astronauts
who traveled to the Moon and back again between 1968 and 1972.
The original photograph, AS17-152-23420, was taken by the
homeward bound crew of
Apollo 17, on December 17, 1972.
For now it's the last picture
of Earth from this planetary perspective taken by
human hands.
APOD: 2021 April 22 - Planet Earth at Twilight
Explanation:
No sudden, sharp boundary marks the passage of day into night in
this gorgeous view
of ocean and clouds over
our fair planet Earth.
Instead, the shadow line or terminator is diffuse and shows
the gradual transition to darkness we experience as twilight.
With the Sun illuminating the scene from the right,
the cloud tops reflect gently reddened
sunlight
filtered
through the dusty troposphere,
the lowest layer of the planet's nurturing atmosphere.
A clear high altitude layer,
visible along the dayside's upper edge,
scatters blue
sunlight and fades into the blackness of space.
This picture was taken in June of 2001 from the International
Space Station orbiting at an altitude of 211 nautical miles.
But you can check out the
vital signs of Planet Earth Now.
APOD: 2021 March 28 - SuitSat 1: A Spacesuit Floats Free
Explanation:
A spacesuit floated away from the
International Space Station 15 years ago,
but no investigation was conducted.
Everyone knew that it was pushed by the
space station crew.
Dubbed
Suitsat-1, the unneeded Russian Orlan spacesuit filled mostly with
old clothes
was fitted with a faint
radio transmitter
and released to orbit the Earth.
The suit
circled the Earth twice before its
radio signal became unexpectedly weak.
Suitsat-1 continued to orbit every 90 minutes
until it burned up in the
Earth's atmosphere after a few weeks.
Pictured, the lifeless spacesuit was photographed in 2006 just as it
drifted away from
space station.
APOD: 2021 January 14 - Aurora Slathers Up the Sky
Explanation:
Like salsa verde on your favorite burrito, a green
aurora
slathers up the sky in this 2017 June 25 snapshot from the
International Space Station.
About 400 kilometers (250 miles) above Earth,
the orbiting station is itself
within the upper realm
of the auroral displays.
Aurorae have the
signature
colors of excited molecules and atoms at the low densities
found at extreme altitudes.
Emission from atomic oxygen dominates this view.
The tantalizing glow
is green at lower altitudes, but rarer reddish
bands extend above the space station's horizon.
The orbital scene
was captured while passing over a point
south and east of Australia, with
stars above the horizon at the right belonging to
the constellation
Canis Major,
Orion's big dog.
Sirius,
alpha star of Canis Major, is the brightest star near
the Earth's limb.
APOD: 2020 November 19 - Crew-1 Mission Launch Streak
Explanation:
Leaving planet Earth
for a moment, a SpaceX Falcon 9 rocket arced
into the early evening sky last Sunday at 7:27 pm EST
from Kennedy Space Center's Launch Complex 39A.
This 3 minute 20 second exposure traces the launch streak
as seen over watery reflections from Port Canaveral, about 15 miles
south of the launch.
The rocket carried four astronauts en route to
the International Space Station on the first flight of a NASA-certified
commercial human spacecraft system.
Dubbed Resilience, the astronauts' Crew Dragon spacecraft successfully docked
with the orbital outpost one day later, on Monday, November 16.
At the conclusion of their six-month stay on the ISS,
the Crew-1 astronauts
will use their spacecraft to return to Earth.
Of course about 9 minutes after launch the Falcon 9 rocket's first stage
returned to Earth, landing in the Atlantic Ocean on autonomous
spaceport drone ship
Just Read The Instructions.
APOD: 2020 June 27 - Eclipse under the ISS
Explanation:
The dark shadow of the New Moon reached out and touched planet Earth on
June 21.
A high definition camera outside
the International Space Station captured its passing in
this snapshot from low Earth orbit
near the border of Kazakhstan and China.
Of course those along the
Moon's central shadow track below could watch
the much anticipated
annular eclipse of the Sun.
In the foreground a cargo spacecraft is docked with the orbital outpost.
It's the H-II Transfer Vehicle-9 from JAXA the
Japan Aerospace Exploration Agency.
APOD: 2020 June 24 - Inverted City Beneath Clouds
Explanation:
How could that city be upside-down?
The city,
Chicago,
was actually perfectly right-side up.
The long shadows it projected onto nearby Lake Michigan near sunset, however,
when seen in reflection, made the buildings appear inverted.
This fascinating, puzzling, yet beautiful
image was captured by a
photographer in 2014 on an airplane on approach to
Chicago's
O'Hare International Airport.
The Sun
can be seen both above and below the cloud deck, with the latter reflected in the
calm lake.
As a bonus, if you look really closely -- and this is quite a challenge --
you can find another airplane in the image, likely also on approach to the same
airport.
APOD: 2020 May 28 - Reflecting the International Space Station
Explanation:
Still bathed in sunlight, the
International Space Station arced through the evening sky over
lake Wulfsahl-Gusborn
in northern Germany, just after sunset on March 25.
The familiar constellation of Orion can be seen left of
the trail of the orbital station's bright passage.
On the right, Venus is the brilliant evening star above the western horizon.
With the camera fixed to a tripod, this scene was captured in
a series of five exposures.
How can you tell?
The short time delay between the end of one exposure and the beginning
of the next leaves small gaps in the
ISS light trail.
Look closely and you'll also see that the sky that appears to be
above the horizon is actually a reflection though.
The final image has been vertically inverted and the
night skyscape recorded in the
mirror-like waters of the small lake.
APOD: 2020 May 13 - Jupiter in Infrared from Gemini
Explanation:
In infrared,
Jupiter lights up the night.
Recently, astronomers at the
Gemini North Observatory in
Hawaii,
USA,
created some of the best
infrared photos
of Jupiter ever taken from Earth’s surface,
pictured.
Gemini was able to produce such a clear image using a technique called
lucky imaging,
by taking many images and combining only the clearest ones that, by chance, were taken when
Earth's atmosphere=/a> was the
most calm.
Jupiter’s
jack-o’-lantern-like
appearance is caused by the planet’s different
layers of clouds.
Infrared light
can pass through clouds better than
visible light,
allowing us to see deeper, hotter layers of
Jupiter's atmosphere,
while the thickest clouds appear dark.
These pictures, together with ones from the
Hubble Space Telescope
and the
Juno spacecraft,
can tell us a lot about weather patterns on Jupiter, like where its
massive, planet-sized storms form.
APOD: 2020 April 24 - Look Up Together
Explanation:
Watch this video.
In only a minute or so you can explore
the night skies around planet Earth through a
compilation of stunning timelapse sequences.
The presentation will take you to sites in the
United States, Germany, Russia, Iran, Nepal, Thailand, Laos and
China.
You might even catch the view from a
small island in the
southeastern Pacific Ocean.
But remember that
while you're home
tonight, the
night sky will come to you.
Look up and celebrate the night during this
International Dark
Sky Week.
APOD: 2020 April 3 - The Traffic in Taurus
Explanation:
There's a traffic jam in Taurus lately.
On April 1, this
celestial frame
from slightly hazy skies over Tapiobicske, Hungary recorded
an impressive pile up toward the zodiacal constellation of the Bull
and the Solar System's ecliptic plane.
Streaking right to left the
International Space Station
speeds across the bottom of the telescopic field of view.
Wandering about
as far from the Sun in planet Earth's skies as it can
get, inner planet Venus is bright and approaching much slower,
overexposed at the right.
Bystanding at the upper left are the sister stars of the Pleiades.
No one has been injured in the close encounter though, because it really
isn't very close.
Continuously occupied since November 2000,
the space station orbits some 400 kilometers
above the planet's surface.
Venus, currently the brilliant evening star,
is almost 2/3 of an
astronomical unit away.
A more permanent resident of Taurus, the Pleiades star cluster is
400 light-years distant.
APOD: 2020 February 20 - Trifecta at Twilight
Explanation:
On February 18, as civil twilight began in northern New Mexico skies,
the International Space Station,
a waning crescent Moon, and
planet Mars for a moment shared
this
well-planned single field of view.
From the photographer's location the sky had just begun to grow light,
but the space station orbiting
400
kilometers above the Earth
was already bathed in the morning sunlight.
At 6:25am local time it took about a second to
cross in front of the lunar disk moving right to left in
the composited successive frames.
At the time, Mars itself
had already emerged from behind the Moon
following its much anticipated lunar occultation.
The yellowish glow of the Red Planet is still in the frame at the
upper right, beyond the Moon's dark edge.
APOD: 2019 October 28 - The Space Station Crosses a Spotless Sun
Explanation:
Typically, the International Space Station is visible only at night.
Slowly drifting across the night sky as it orbits the Earth, the
International Space Station (ISS) can be seen as a
bright spot about once a month from many locations.
The ISS is then visible only just after sunset or just before sunrise because it shines by reflected sunlight -- once the ISS enters the Earth's shadow, it will drop out of sight.
The only occasion when the
ISS is visible during the day is when it
passes right in front of the Sun.
Then, it passes so quickly that only cameras
taking short exposures can visually freeze the
ISS's silhouette onto the background
Sun.
The
featured picture did exactly that -- it is actually a series of images taken a month ago from
Santa Fe,
Argentina with perfect timing.
This image series was later combined with a separate image
highlighting the texture of the spotless Sun, and an image bringing up the
Sun's prominences around the edge.
At an unusually low
Solar Minimum, the Sun has gone
without sunspots now for most of 2019.
APOD: 2019 October 19 - All Female Spacewalk Repairs Space Station
Explanation:
The failed unit was beyond the reach of the robotic
Canadarm2.
Therefore, this repair of the
International Space Station would require humans.
The humans on duty were NASA's
Jessica Meir
and
Christina Koch.
This was the fourth spacewalk for Koch, the first for Meir, and the
first all-female spacewalk in human history.
The first woman to walk in space was
Svetlana Savitskaya in 1984.
Koch (red stripe) and Meir are
pictured hard at work on the
P6 Truss,
with solar panels and the darkness of space in the background.
Working over seven hours, the newly installed
Battery Charge / Discharge Unit (BCDU) was successfully replaced and, when powered up, operated normally.
APOD: 2019 July 15 - The Space Station Crosses a Spotless Sun
Explanation:
That's no sunspot.
It's the
International Space Station (ISS)
caught passing in front of the Sun.
Sunspots, individually, have a dark central
umbra, a lighter surrounding penumbra, and
no solar panels.
By contrast, the ISS is a complex and multi-spired mechanism,
one of the largest and most sophisticated machines ever created by
humanity.
Also, sunspots occur on the
Sun,
whereas the
ISS orbits the
Earth.
Transiting the Sun is not very unusual for the
ISS, which orbits the Earth about every 90 minutes,
but getting one's timing and equipment just right for a
great image is rare.
Strangely, besides that fake spot, in this recent two-image composite, the Sun
lacked any real sunspots.
The featured picture combines two images -- one capturing the space station transiting the Sun -- and another taken consecutively capturing details of the Sun's surface.
Sunspots have been
rare on the
Sun
since the dawn of the current
Solar Minimum,
a period of low solar activity.
For reasons not yet fully understood, the
number of sunspots occurring during both the previous and current solar minima have been
unusually low.
APOD: 2019 June 2 - A Live View from the International Space Station
Explanation:
If you were floating above the Earth right now, this is what you might see.
In 2014, a robotic
SpaceX
Dragon capsule
that delivered supplies to the Earth-orbiting
International Space Station (ISS) also delivered High Definition Earth Viewing
(HDEV) cameras that take and transmit live views of Earth.
Pictured here,
when working, is the live video feed that switches between four cameras, each pointed differently.
Watch white clouds, tan land, and
blue oceans drift by.
The featured live view will appear black when it is
nighttime on the Earth below,
but the space station's
rapid 90-minute orbit
compresses this dark time into only 45 minutes.
The present location of the ISS above the Earth can be found
on the web.
If the video appears gray, this indicates that the view is either being switched between cameras, or communications with the ISS is temporarily unavailable.
As the HDEV project continues, video quality will be monitored to assess the effects of high energy radiation, which types of cameras work best, and which
Earth views are the most popular.
APOD: 2019 May 16 - Dark Skies: Turn on the Night
Explanation:
Have you ever experienced a really dark night sky?
One common and amazing feature is the glowing band of our
Milky Way galaxy stretching from horizon to horizon.
If you live in or near a big city, though, you might not know this
because city lights reflecting off the
Earth's atmosphere could only
allow you to see the Moon and a few stars.
Today, however, being
UNESCO's
International Day of Light, the
International Astronomical Union is asking people to
Turn on the Night by trying to better understand,
and in the future better reduce,
light pollution.
You can practice even now by going to the main
APOD website at NASA
and hovering your cursor over the
Before image.
The
After
picture that comes up is a panorama of four exposures
taken with the same camera and from the same location, showing what
happened recently in
China when people in
Kaihua County
decided to turn down many of their lights.
Visible in the
Before picture
are the stars Sirius (left of center) and Betelgeuse, while visible in the
After picture
are thousands of stars with the arching band of our Milky Way Galaxy.
Humanity has lived for millennia under a
dark night sky,
and connecting to it has
importance for both natural and cultural heritage.
APOD: 2019 May 11 - Milky Way, Launch, and Landing
Explanation:
The Milky Way doesn't look quite this colorful and bright to the eye,
but a rocket launch does.
So a separate deep exposure with a sensitive digital camera was used in
this composite skyscape to bring out our galaxy's central crowded
starfields and cosmic dust clouds.
In the scene from Merritt Island National Wildlife Refuge, a nine
minute long exposure begun about 20 minutes after the
Miky Way image recorded a rocket
launch and
landing.
The Falcon 9 rocket, named for the Millennium Falcon of Star Wars fame,
appropriately launched a
Dragon
resupply ship to the International Space Station
in the early morning hours of May the 4th.
The plume and flare at the peak of the launch arc mark the rocket's
first stage boost back burn.
Two shorter diagonal streaks are the rocket engines bringing the Falcon 9 stage
back to an offshore landing on autonomous drone ship
Of course I Still Love You.
APOD: 2019 May 2 - Manicouagan Impact Crater from Space
Explanation:
Orbiting 400 kilometers above Quebec, Canada, planet Earth, the
International Space Station
Expedition 59 crew captured this snapshot of the broad
St. Lawrence River and curiously circular Lake Manicouagan on April 11.
Right of center, the ring-shaped lake is a
modern
reservoir within the eroded remnant of an ancient 100 kilometer
diameter impact crater.
The ancient crater is very
conspicuous from orbit,
a visible reminder that Earth is vulnerable to
rocks from space.
Over 200 million years old, the Manicouagan crater was
likely caused by the impact of a rocky body about
5 kilometers in diameter.
Currently, there is no known asteroid with a significant probability of
impacting Earth in the next century.
But a fictional scenario to help
practice for an
asteroid impact is
on going
at the 2019 IAA
Planetary Defense Conference.
APOD: 2019 April 2 - Space Station Silhouette on the Moon
Explanation:
What's that unusual spot on the Moon?
It's the
International Space Station.
Using precise timing, the
Earth-orbiting space platform
was photographed in front of a partially lit
gibbous Moon last month.
The featured image was taken from
Palo Alto,
California,
USA with an exposure time of only
1/667 of a second.
In contrast, the duration of the transit of the
ISS across the entire Moon was about
half a second.
A close inspection of this unusually
crisp ISS silhouette will reveal the outlines of
numerous solar panels and trusses.
The bright
crater Tycho is visible on the lower left,
as well as comparatively rough,
light colored terrain known as
highlands, and relatively smooth, dark colored areas known as
maria.
On-line
tools can tell you when the
International Space Station will be visible from your area.
APOD: 2019 March 13 - Highlights of the North Spring Sky
Explanation:
What can you see in the night sky this season?
The featured graphic gives a few highlights for
Earth's northern hemisphere.
Viewed as a clock face centered at the bottom, early (northern) spring sky events fan out toward the left, while late spring events are projected toward the right.
Objects relatively close to
Earth
are illustrated, in general, as nearer to the cartoon figure with the telescope at the bottom center -- although almost
everything pictured
can be seen without a telescope.
As happens during any season, constellations appear the same year to year, and, as usual, the
Lyrids meteor shower will peak in mid-April.
Also as usual, the
International Space Station (ISS)
can be seen, at times, as a bright spot
drifting across the sky after sunset.
After the
Vernal Equinox next week, the length of daytime will be greater than the length of nighttime in Earth's northern hemisphere, an inequality that will escalate as the
spring season
develops.
Also as spring ages,
Jupiter becomes visible increasingly earlier in the night.
As spring draws to a close, the month of May will feature
the third of four full moons of the season, one of the definiitions of a
Blue Moon.
APOD: 2018 September 25 - Highlights of the North Autumn Sky
Explanation:
What can you see in the night sky this season?
The featured graphic gives a few highlights for Earth's northern hemisphere.
Viewed as a clock face centered at the bottom, early (northern) autumn sky events fan out toward the left, while late autumn events are projected toward the right.
Objects relatively close to
Earth
are illustrated, in general, as nearer to the cartoon figure with the telescope at the bottom center -- although almost everything pictured can be
seen without a telescope.
As happens during any season, constellations appear the same year to year, and, as usual, the
Leonids meteor shower will peak in mid-November.
Also as usual, the
International Space Station (ISS)
can be seen, at times, as a bright spot
drifting across the sky after sunset.
Planets visible after sunset this autumn include
Jupiter and Mars, and during late autumn,
Saturn.
APOD: 2018 May 29 - Aurora and Manicouagan Crater from the Space Station
Explanation:
How many of these can you find in today's featured photograph: an aurora, airglow, one of the oldest impact craters on the Earth, snow and ice, stars, city lights, and part of the International Space Station?
Most of these can be identified by their distinctive colors.
The aurora
here appears
green at the bottom, red at the top,
and is visible across the left of image.
Airglow appears orange and can be seen hovering over the
curve of the Earth.
The circular Manicouagan Crater in
Canada, about 100 kilometers across and 200 million years old, is visible toward the lower right and is covered in white
snow and ice.
Stars, light in color, dot the
dark background of space.
City lights appear a bright yellow and dot the landscape.
Finally, across the top, part of the
International Space Station (ISS) appears mostly tan.
The
featured image was taken from the
ISS in 2012.
APOD: 2018 May 1 - The Aurora and the Sunrise
Explanation:
On the International Space Station (ISS),
you can only admire an aurora until the sun rises.
Then the background Earth becomes too bright.
Unfortunately, after
sunset, the rapid orbit of the ISS around the Earth means that sunrise is usually less than
47 minutes away.
In the
featured image, a green aurora is visible below the
ISS -- and on the horizon to the upper right, while sunrise approaches ominously from the upper left.
Watching an aurora from space can be
mesmerizing as its changing shape has been compared to a giant green amoeba.
Auroras are composed of energetic electrons and protons from the Sun that impact the
Earth's magnetic field and then
spiral down toward the Earth so fast that they cause
atmospheric atoms and molecules to glow.
The ISS orbits at nearly
the same height as auroras, many times
flying right through an aurora's thin upper layers,
an event that neither harms astronauts nor
changes the shape of the aurora.
APOD: 2018 March 12 - Flying over the Earth at Night II
Explanation:
What would it be like to orbit the Earth?
The International Space Station (ISS) does this every 90 minutes,
and sometimes the astronauts on board
take image sequences that are
made into videos.
The
featured time-lapse video shows many visual spectacles of the
dark Earth below.
First, as the video begins,
green and red auroras are visible on the upper left above white clouds.
Soon city lights come into view, and it
becomes clear you are flying over
North America,
eventually passing over
Florida.
In the second sequence you fly over
Europe and
Africa, eventually passing over the
Nile River.
Brief flashes of light are
lightning in
storms.
Stars far in the distance can be seen rising through the
greenish-gold glow of the
Earth's atmosphere.
APOD: 2018 February 17 - Manhattan Skylines
Explanation:
City lights shine along the upper east side of Manahattan in
this dramatic urban night skyscape from February 13.
Composed from a series of digital exposures, the monochrome
image is reminiscent of the time
when sensitive black and white film was a popular choice for dimly
lit night and astro-photography.
Spanning 2 minutes and 40 seconds, the combined 22 frames
look across the reservoir in
New
York City's Central Park.
Stars trail in the time-lapse view while drifting clouds
make patterns in the sky.
Traced from top to bottom, the dashed line in the surreal scene is the
International Space Station still in sunlight and
heading for the southeast horizon.
The short time intervals between the exposures leave
gaps in the space station's bright trail.
APOD: 2017 May 2 - Approach above Sunset
Explanation:
There it is!
The Cygnus supply ship was a welcome sight to the astronauts on the
International Space Station just over a week ago.
Launched three days before on a
United Launch Alliance
Atlas V from
Cape Canaveral, Florida, the
Orbital ATK's
Cygnus spacecraft
approached the
International Space Station above the backdrop of a picturesque planet Earth.
The Sun was setting off
the image to the upper left, illuminating clouds well below the approaching vehicle.
The robotic
Cygnus spacecraft
was captured first on camera and
later with the space station's
Canadarm2
by ESA's Flight Engineer
Thomas Pesquet and NASA's
Expedition-51 Commander
Peggy Whitson.
Commander
Whitson, a
biochemist, has now set a
new American record for the most total days in space.
Besides essentials, the Cygnus carried equipment to bolster over 200
science experiments
being conducted on the football-field sized
Earth-orbiting outpost.
APOD: 2016 December 22 - An Airplane Glory
Explanation:
Looking out the window of an airplane,
you might be lucky enough to see "the glory"
in the direction directly opposite the Sun.
Before airplanes, the phenomenon, known to some as the
heiligenschein or the
Specter of the Brocken,
was sometimes seen from mountaintops.
There, when conditions were right, one could
look away from the Sun
and see what appeared to be the
shadow of a giant
surrounded by a bright
halo.
The giant turns out to be the observer,
as in the modern version a
silhouette of an airplane
frequently occupies the glory's center.
This bright
glory
was photographed two weeks ago over
Michigan from an airplane
on approach to
O'Hare International Airport.
The cause of the glory is still being researched
and is
relatively complex.
Surely, small droplets of water in some way
reflect, refract, and diffract sunlight backwards towards the
Sun.
The phenomenon has similar counterparts in
other branches of science including
astronomy, where looking out from the Earth
in the direction opposite the Sun yields a
bright spot called
the gegenschein.
APOD: 2016 November 5 - ISS Fisheye Flythrough
Explanation:
Shot
in Ultra HD, this stunning video can take you on a tour of the
International Space Station.
A fisheye lens with sharp focus and extreme depth of field provides
an immersive visual experience of life in the orbital outpost.
In the 18 minute fly-through, your point of view will float serenely
while you watch our fair planet go by 400 kilometers
below the seven-windowed Cupola,
and explore the interior of the station's habitable nodes and modules from
an astronaut's perspective.
The modular International Space Station is Earth's largest
artificial satellite,
about the size of a football field in overall length and width.
Its total
pressurized volume is approximately equal
to that of a Boeing 747 aircraft.
APOD: 2016 October 9 - Hurricane Ivan from the Space Station
Explanation:
Ninety percent of the houses on
Grenada were
damaged by the destructive force of
Hurricane Ivan.
At its peak in 2004,
Ivan was a
Category 5 hurricane,
the highest power category on the
Saffir-Simpson Scale,
and created sustained
winds
in excess of 200 kilometers per hour.
Ivan was the largest
hurricane to strike the US in 2004, and one of the more powerful in recorded history.
As it swirled in the
Atlantic Ocean,
the tremendous
eye of Hurricane Ivan was
photographed from above by the orbiting
International Space Station.
The name Ivan has now been retired from Atlantic Ocean use by the
World Meteorological Organization.
This month,
Hurricane Matthew devastated part of
Haiti and is
currently swirling just off the east coast of the
USA.
APOD: 2016 September 2 - Little Planet Astro Camp
Explanation:
Day and night on this little planet
look a lot like day and night on planet Earth.
In fact, the images used to construct the little planet projection,
a digitally warped and stitched mosaic covering 360x180 degrees, were
taken during day and night near Tarján, Hungary, planet Earth.
They span a successful
33-hour-long
photo experiment at July's
Hungarian Astronomical Association Astro Camp.
The time-series composite follows the solar disk in 20 minute
intervals from sunrise to sunset and over six hours of star trails
in the northern night sky centered on the
North Celestial Pole near bright star Polaris.
The orbiting
International
Space Station traced the offset arc
across the northern night.
Below the little planet's nightside horizon, red light lamps
of fellow astro-campers left the
night-long, dancing trails.
APOD: 2016 June 16 - Northern Lights above Lofoten
Explanation:
The Aurora Borealis
or northern lights are familiar visitors to
night skies above the village of Reine in the Lofoten Islands,
Norway, planet Earth.
In this scene, captured from a mountaintop camp site, the
auroral curtains do seem to create an eerie tension with the
coastal lights though.
A modern perspective on the
world at night, the stunning image was chosen as the
over all winner in The World at Night's 2016 International
Earth and
Sky Photo Contest.
Selections were made from over 900 entries highlighting the beauty
of the night sky and its battle with
light
pollution.
APOD: 2016 May 13 - ISS and Mercury Too
Explanation:
Transits of Mercury are relatively rare.
Monday's leisurely 7.5 hour long event was only the 3rd of 14 Mercury
transits in the 21st century.
If you're willing to travel,
transits of the International
Space Station can be more frequent though, and much quicker.
This sharp
video frame composite was taken from a well-chosen location
in Philadelphia, USA.
It follows the space station, moving from upper right to lower
left, as it crossed the Sun's disk in 0.6 seconds.
Mercury
too is included as the small, round, almost stationary
silhouette just below center.
In apparent size, the International Space Station looms larger
from low Earth orbit,
about 450 kilometers from Philadelphia.
Mercury was about 84 million kilometers away.
(Editor's note:
The stunning
video includes another
double transit, Mercury and a Pilatus PC12 aircraft. Even quicker
than the ISS to cross the Sun, the aircraft was about 1 kilometer
away.)
APOD: 2016 April 18 - The International Space Station over Earth
Explanation:
The International Space Station is the largest object ever constructed by humans in space.
The station perimeter extends over roughly the area of a
football field, although only a small fraction of this is composed of modules habitable by humans.
The station is so large that it could not be
launched all at once --
it continues to be
built piecemeal.
To function, the
ISS needs huge
trusses, some over 15 meters long and with masses over 10,000 kilograms, to keep it rigid and to route
electricity and liquid
coolants.
Pictured above, the immense
space station was photographed
from the now-retired space shuttle Atlantis after a week-long stay in 2010.
Across the image top hangs part of a bright blue Earth, in stark contrast to the darkness of
interstellar space across the bottom.
APOD: 2016 February 24 - USA's Northeast Megalopolis from Space
Explanation:
Can you identify a familiar area in the northeast USA just from nighttime lights?
It might be possible because many major cities are visible, including (right to left)
New York,
Philadelphia,
Baltimore,
Washington,
Richmond and
Norfolk --
Boston of the USA's
Northeast megalopolis is not pictured.
The featured image was taken in 2012
from the
International Space Station.
In the foreground are two
Russian cargo ships with prominent
solar panels.
This Northeast megalopolis of the USA contains almost 20 percent of the people of the
USA but only about 2 percent of the land area.
Also known also as the
Northeast Corridor
and part of the
Eastern Seaboard,
about 10 percent of the world's largest companies are headquartered here.
The near continuity
of the lights seem to add credence to the 1960s-era prediction that the entire stretch is evolving into
one continuous city.
APOD: 2015 November 9 - Assembly of The International Space Station
Explanation:
It is the largest and most sophisticated object ever built off the Earth.
It has taken numerous spaceflights and over a decade to
construct.
The International Space Station
(ISS) is currently the
premiere habitat for humans in Earth orbit, and an amalgamation of sophisticated orbiting laboratories that have examined everything from the formation of
new materials and medicines created in
microgravity -- to the limitations of the human body -- to the
composition of the universe.
This month, the
ISS is
celebrating 15 years of continuous human habitation.
The ISS has been visited by astronauts from 15 countries, so far, and has
international partners led by
NASA (USA),
Roscosmos (Russia),
CSA (Canada),
JAXA (Japan), and
ESA (Europe).
The featured animation
shows the piece-by-piece construction of the
ISS from 1998 to 2011.
Spanning the length of a football field, the
ISS can be
seen as an unusually
bright spot drifting slowly overhead by anyone who knows
when and where to look.
APOD: 2015 July 22 - Gamma ray Rain from 3C 279
Explanation:
If gamma-rays were raindrops a flare from a
supermassive black hole might look like this.
Not so gently falling on the
Fermi
Gamma-ray Space Telescope from June 14 to June 16 the
gamma-ray
photons, with energies up to 50 billion electron volts,
originated in active galaxy 3C 279 some 5 billion light-years away.
Each gamma-ray "drop" is an expanding circle in the
timelapse visualization, the color and maximum size determined by the
gamma-ray's
measured energy.
Starting with a background drizzle, the sudden downpour
that then trails off is the intense, high energy flare.
The
creative and calming presentation of the historically bright
flare covers a 5 degree wide region of
the gamma-ray sky centered on 3C 279.
APOD: 2015 April 27 - Space Station over Lunar Terminator
Explanation:
What's that in front of the Moon?
It's the International Space Station.
Using precise timing, the
Earth-orbiting space platform
was photographed in front of a partially lit Moon last year.
The featured image was taken from
Madrid,
Spain
with an exposure time of only 1/1000 of a second.
In contrast, the duration of the transit of the
ISS across the entire Moon was about
half a second.
The sun-glinting
station can be seen
just to the dark side of the day / night line known as the
terminator.
Numerous circular
craters
are visible on the distant Moon, as well as comparatively rough,
light colored terrain known as
highlands, and relatively smooth, dark colored areas known as
maria.
On-line
tools can tell you when the International Space Station will be visible from your area.
APOD: 2015 March 2 - Lenticular Cloud, Moon, Mars, Venus
Explanation:
It is not every day that such an interesting cloud
photobombs your image.
The original plan was to photograph a rare angular
conjunction
of
Mars and Venus that occurred a week and a half ago,
with the added bonus of a crescent Moon and the
International Space Station (ISS) both passing nearby.
Unfortunately, on
Madeira Island,
Portugal,
this event was clouded out.
During the next day, however, a spectacular
lenticular cloud appeared before sunset, so the
industrious astrophotographer
quickly formulated a new plan.
A close look at the
resulting image reveals the Moon visible toward the left of the frame, while underneath, near the bottom, are the famous planets with Venus being the brighter.
It was the unexpected
lenticular cloud, though, perhaps looking like some sort of futuristic
spaceship, that stole the show.
The setting Sun illuminated the stationary cloud (and everything else) from the bottom, setting up an intricate pattern of shadows, layers, and brightly illuminated regions, all seen evolving in a
corresponding video.
Mars and Venus will
next appear this close on the sky in late August,
but whether any place on Earth will catch them behind such a photogenic cloud is unknown.
APOD: 2014 December 6 - Orion Launch
Explanation:
Headed for two orbits of planet Earth and a splashdown in the Pacific,
Orion
blazed into the early morning sky on Friday at 7:05am ET.
The
spacecraft was launched atop a United
Launch Aliance Delta IV Heavy rocket from Cape Canaveral
Air Force Station in Florida.
Its first voyage
into space on an uncrewed flight test,
the Orion traveled some 3,600 miles from Earth, about 15 times higher
than the orbital altitude of the International Space Station.
In fact, Orion traveled
farther
into space than any spacecraft designed
for astronauts since the Apollo missions
to the Moon.
The Orion crew module reached speeds of 20,000 miles per hour
and temperatures approaching 4,000 degrees Fahrenheit
as it re-entered Earth's atmosphere about 4.5 hours after launch.
APOD: 2014 October 6 - Space Station Detector Finds Unexplained Positron Excess
Explanation:
Where did all these high energy positrons come from?
The Alpha Magnetic Spectrometer (AMS-02) onboard the
International Space Station (ISS)
has been meticulously recording how often it is struck by both high energy electrons and
positrons since 2011.
After accumulating years of data, it has now become clear
that there are significantly more positrons than expected
at the highest energies detected.
The excess may have a very exciting and profound origin -- the annihilation of distant but previously undetected dark matter particles.
However, it is also possible that astronomical sources such as
pulsars
are creating the
unexplained discrepancy.
The topic remains a very active area of research.
Pictured here, the
AMS is visible on the ISS just after being installed, with a US
Space Shuttle docked on the far right, a Russian
Soyuz capsule docked on the far left, and the
blue Earth that houses all nations visible across the background.
APOD: 2014 September 27 - A Launch and a Landing
Explanation:
Taken from an Atlantic beach, Cape Canaveral,
planet Earth,
four identically framed digital images are combined in this
night skyscape.
Slightly shifted short star trails dot the sky, but the
exposure times were adjusted to follow the flight
of a Falcon 9 rocket.
The September 21
launch delivered a Dragon X capsule filled with
supplies to the International Space Station.
Above the bright flare seen just after launch,
the rocket's first stage firing trails upward from the left.
After separation, the second stage burn begins near center with
the vehicle climbing toward low Earth orbit.
At the horizon, the flare near center records the re-ignition
and controlled descent of the
Falcon 9's first stage
to a soft splashdown off the coast.
APOD: 2014 August 3 - Dark Shuttle Approaching
Explanation:
What's that approaching?
Astronauts on board the
International Space Station
first saw it in early 2010 far in the distance.
Soon it enlarged to become a
dark silhouette.
As it came even closer, the
silhouette appeared to be a spaceship.
Finally, the object revealed itself to be the
Space Shuttle Endeavour, and it soon docked as expected with the
Earth-orbiting space station.
Pictured above, Endeavour was imaged near Earth's horizon as it approached, where several layers of the
Earth's atmosphere were visible.
Directly behind the shuttle is the
mesosphere, which appears blue.
The atmospheric layer that appears white is the
stratosphere,
while the orange layer is Earth's
Troposphere.
This shuttle mission, began with a
dramatic night launch.
Tasks completed during this shuttle's visit to the
ISS included the delivery of the
Tranquility Module which contained a
cupola bay window complex that allows
even better views of spaceships approaching and leaving the space station.
APOD: 2014 June 28 - Orion Arising
Explanation:
Orion's belt runs just along the horizon, seen
through Earth's atmosphere and rising in
this
starry snapshot from low Earth orbit
on board the International Space Station.
The belt stars,
Alnitak, Alnilam, and Mintaka
run right to left
and Orion's sword,
home to the great Orion Nebula, hangs above his belt,
an orientation unfamiliar to
denizens of the planet's
northern hemisphere.
That puts
bright star Rigel, at the foot of Orion,
still higher above Orion's belt.
Of course the brightest celestial beacon in
the frame is Sirius, alpha star of the
constellation Canis Major.
The station's
Destiny Laboratory module is in the foreground
at the top right.
APOD: 2014 May 25 - Camelopardalids and ISS
Explanation:
From a camp on the northern shores of the Great Lake Erie, three
short bright meteor streaks were captured in this composited
night skyscape.
Recorded over the early morning hours of May 24, the meteors are
elusive Camelopardalids.
Their trails point back to the meteor shower's radiant near
Polaris, in the large but faint constellation
Camelopardalis
the camel leopard, or in modern terms the Giraffe.
While
a few meteors did appear,
the shower
was not an active
one as the Earth crossed through the predicted debris trail
of periodic comet 209P/LINEAR.
Of course, the long bright streak in the image did appear as
predicted.
Early on May 24, the International Space Station made a
bright passage through northern skies.
APOD: 2014 May 14 - A Live View from the International Space Station
Explanation:
If you were floating above the Earth right now, this is what you might see.
Two weeks ago, the robotic
SpaceX
Dragon capsule
that delivered supplies to the Earth-orbiting
International Space Station (ISS) also delivered
High Definition Earth Viewing
(HDEV) cameras that take and transmit live views of Earth.
Pictured above,
when working, is the live video feed that switches between four cameras, each pointed differently.
Watch white clouds, tan land, and
blue oceans drift by.
The above video
will appear black when it is
nighttime on the Earth below,
but the space station's
rapid 90-minute orbit
compresses this dark time into only 45 minutes.
The present location of the ISS above the Earth can be found
on the web.
If the video appears gray, this indicates that the view is either being switched between cameras, or communications with the ISS is temporarily unavailable.
As the HDEV project continues, video quality will be monitored to assess the effects of high energy radiation, which types of cameras work best, and which
Earth views are the most popular.
Although this feed will eventually be terminated,
lessons learned will enable better cameras to be deployed to the ISS in the future,
likely returning even more interesting live feeds.
APOD: 2014 April 1 - Space Station Robot Forgets Key Again
Explanation:
Space station robot AFJ013 has forgotten her space lock key again.
The
frustrated robot was reduced to tapping on a
space station window and asking for a
human to let her back in -- for the third time this week.
"Yes, she did a great job adjusting the tolerances on the new
science module, but why she can't remember to take her key is beyond me,"
said incredulous station commander
Koichi Wakata
(Japan).
"We would keep the entry unlocked but we are afraid that space aliens will
come in and
raid our refrigerator", the astronaut lamented.
Happy April Fools' Day from the
folks at APOD.
In reality,
International Space Station astronaut
Wakata
poses in front of a
Cupola window while the
Latching End Effector, attached to
Canadarm2,
is visible just outside.
APOD: 2014 January 6 - Three CubeSats Released
Explanation:
Cubes are orbiting the Earth.
Measuring ten-centimeters on a side,
CubeSats --
each roughly the size of a large
coffee mug --
are designed to be inexpensive both to build and to launch.
Pictured above, three CubeSats were released from the
International Space Station
(ISS) last November by the arm of the
Japanese
Kibo Laboratory module.
CubeSats are frequently created by students as part of university science or
engineering projects and include missions such as collecting
wide angle imagery of the Earth,
testing orbital radio communications, monitoring the
Earth's magnetic field, and
exploring the Earth's
surrounding radiations.
Depending on the exact height of their release,
CubeSats will re-enter the
Earth's atmosphere
on the time scale of months to years.
APOD: 2014 January 2 - Reflections on Planet Earth
Explanation:
Catching sight of
your reflection in
a store window or shiny hubcap can be
entertaining and occasionally even inspire a
thoughtful
moment.
So consider this reflective view
from 300 kilometers above planet Earth.
The picture is actually a self-portrait
taken by astronaut
Michael Fossum on July 8, 2006 during a space walk or extravehicular
activity while the
Discovery orbiter was docked with the
International Space Station.
Turning his camera to snap a picture of his own helmet visor,
he also recorded the reflection of his fellow
mission specialist,
Piers Sellers, near picture center and one of the space station's
gold-tinted solar power arrays arcing across the top.
Of course, the horizon of
our fair planet
lies in background.
APOD: 2013 December 6 - Gamma Ray Earth and Sky
Explanation:
For an Earth-orbiting gamma-ray telescope,
Earth is actually the brightest source of
gamma-rays, the most energetic form of light.
Gamma-rays from Earth
are produced when high energy particles,
cosmic rays
from space, crash into the atmosphere.
While that interaction blocks harmful radiation from
reaching the surface, those gamma-rays dominate
in this remarkable Earth and sky view
from the orbiting
Fermi
Gamma-ray Space Telescope's Large Area Telescope.
The image was constructed using only observations
made when the center of our Milky Way galaxy was near the zenith,
directly above the
Fermi satellite.
The zenith is mapped to the center of the field.
The Earth and points near the nadir, directly below the satellite,
are mapped to the edges of the field resulting
in an Earth and all-sky projection
from Fermi's orbital perspective.
The color scheme shows low intensities of gamma-rays
as blue and high intensities as yellowish hues on a
logarithmic scale.
Our fair planet's
brighter gamma-ray glow floods the edges of field,
the high intensity yellow ring tracing Earth's limb.
Gamma-ray sources
in the sky along the relatively faint Milky Way
stretch diagonally across the middle.
Launched June 11, 2008 to
explore the
high-energy Universe,
this week Fermi celebrated its 2,000th day in low Earth orbit.
APOD: 2013 July 8 - Pluto's Newly Discovered Moons Receive Names
Explanation:
Pluto's newly discovered moons now have names.
Known previously as
P4 and P5, the
International Astronomical Union has now
given the fourth and fifth discovered moons of
Pluto the names
Kerberos
and Styx.
The small moons were discovered in 2011 and 2012 by the
Hubble Space Telescope in preparation for the close passing of the
New Horizons spacecraft by Pluto in 2015.
Kerberos
is named for the
many headed dog in
Greek mythology that guards the entrance to the underworld, while
Styx is named for the
goddess who overlooks the
mythological river that runs between the Earth and the underworld.
Both monikers are related to the name of Pluto, who rules the
mythical nether region.
Because their reflectivity is unknown, the size of each moon is quite uncertain -- but each is crudely estimated to be about 20 kilometers in diameter.
The robotic New Horizons spacecraft is on schedule to pass by Pluto in 2015 and provide the first clear images of the
dwarf planet and its companions.
APOD: 2013 April 24 - Wringing a Wet Towel in Orbit
Explanation:
What happens if you wring out a wet towel while floating in space?
The water shouldn't fall toward the floor because while orbiting the
Earth, free falling objects will appear to float.
But will the water fly out from the towel, or what?
The answer may surprise you.
To find out and to further exhibit how strange being in orbit can
be,
Expedition 35
Commander
Chris Hadfield
did just this experiment last week in the
microgravity
of the Earth orbiting
International Space Station.
As demonstrated in the
above video, although a few drops do go flying
off, most of the water sticks together and forms a unusual-looking cylindrical
sheath in and around the towel.
The self-sticking
surface tension
of water is well known on Earth, for
example being used to create
artistic water cascades
and, more generally,
raindrops.
APOD: 2013 April 6 - Earth at Twilight
Explanation:
No sudden, sharp boundary marks the passage of day
into night in
this gorgeous view
of ocean and clouds over
our fair
planet Earth.
Instead, the shadow line or
terminator is
diffuse and shows
the gradual transition to darkness we experience as twilight.
With the Sun illuminating the scene from the right,
the cloud tops reflect gently reddened
sunlight
filtered
through the dusty troposphere, the lowest layer of the planet's
nurturing atmosphere.
A clear high altitude layer,
visible along the dayside's upper edge,
scatters blue
sunlight and fades into the blackness of space.
This picture actually is a single digital
photograph taken in June of 2001 from the
International Space Station orbiting
at an altitude of 211
nautical
miles.
APOD: 2013 March 31 - Flying Over the Earth at Night
Explanation:
Many wonders are visible when flying over the Earth at night.
A compilation of such visual spectacles was
captured recently
from the
International Space Station (ISS) and set to
rousing music.
Passing below are
white clouds,
orange city lights,
lightning flashes in thunderstorms, and dark
blue seas.
On the horizon is the
golden haze of Earth's thin atmosphere,
frequently decorated by
dancing auroras as the video progresses.
The green parts of
auroras typically remain below the space station, but the
station flies right through the red and purple auroral peaks.
Solar panels of the ISS are seen around the frame edges.
The ominous wave of approaching brightness at the end of each sequence is just the
dawn of the sunlit half of Earth, a dawn that occurs
every 90 minutes.
APOD: 2013 February 1 - Atlas V Launches TDRS-K
Explanation:
Beyond a fertile field of satellite communication antennas at
Kennedy
Space Center, an Atlas V rocket
streaks into orbit in
this long exposure photograph.
In the thoughtfully
composed image recorded on the evening of January 30,
the antennas in the foreground bring to mind the rocket's payload, a
Tracking
and Data Relay Satellite (TDRS; sounds like TEE-dress).
This TDRS-K is the first in a next-generation series
adding to the constellation of NASA's communication satellites.
Operating from geosynchronous orbit
22,300 miles (36,000 kilometers) above planet Earth,
the network of TDRS satellites relays
communications, data, and commands between
spacecraft and ground stations.
Formerly the TDRS network provided communications for
space shuttle missions.
In fact,
many TDRS
satellites were ferried as far as low Earth orbit on
space shuttles.
The TDRS network continues to support major spacecraft like the
International Space Station, the
Hubble Space Telescope, and the
Fermi Gamma-ray Space Telescope.
APOD: 2013 January 24 - ISS and the Summer Milky Way
Explanation:
Clouds on
a summer night
frame this sea and skyscape, recorded earlier
this month near Buenos Aires, Argentina.
But planet Earth's
clouds are not the only clouds on the scene.
Starry clouds and nebulae along the southern hemisphere's summer
Milky Way arc above the horizon, including
the dark Coal Sack
near the Southern Cross and the
tantalizing pinkish glow of the Carina Nebula.
Both the Large (top center) and Small Magellanic Clouds
are also in view, small galaxies in their own right and
satellites
of the Milky Way
up to 200,000 light-years distant.
Alpha star of the Carina constellation and second
brightest star in Earth's night,
Canopus
shines above about 300 light-years away.
Still glinting
in sunlight at an altitude of 400 kilometers,
the orbiting International Space Station traces a
long
streak through the single, 5 minute, star-tracking exposure.
APOD: 2012 September 18 - Orbiting Astronaut Self Portrait
Explanation:
Is it art?
Earlier this month, space station astronaut
Aki Hoshide
(Japan) recorded
this striking image while helping to augment the capabilities of the Earth-orbiting
International Space Station (ISS).
Visible in this outworldly assemblage is the Sun,
the Earth, two portions of a robotic arm, an astronaut's spacesuit,
the deep darkness of space, and the unusual camera taking the picture.
This image joins other historic -- and possibly
artistic --
self-portraits
taken
previously in space.
The Expedition 32 mission
ended yesterday when an attached capsule undocked with the ISS and
returned some of the crew to Earth.
APOD: 2012 August 29 - A Dark Earth with a Red Sprite
Explanation:
There is something very unusual in this picture of the Earth -- can you find it?
A fleeting phenomenon once thought to be only a legend has been newly caught if you know just where to look.
The above image
was taken from the orbiting
International Space Station (ISS)
in late April and shows familiar ISS solar panels on the far left and part of a robotic arm to the far right.
The rarely imaged phenomenon is known as a
red sprite and it
can be seen,
albeit faintly, just over the bright area on the image right.
This bright area and the red sprite
are different types of lightning,
with the white flash the more typical type.
Although sprites have been reported
anecdotally for as long as 300 years, they were first caught on film in 1989 -- by accident.
Much remains unknown about
sprites including how they occur, their effect on the atmospheric
global electric circuit,
and if they are somehow related to other
upper atmospheric lightning
phenomena such as
blue jets or
terrestrial gamma flashes.
APOD: 2012 July 28 - Trails in the Morning Sky
Explanation:
Brilliant Venus and bright Jupiter still rise
together before dawn.
The peaceful
waters by a small
lakeside
house near Stuttgart, Germany
reflect their graceful arcing trails in this composited series of
exposures, recorded on the morning of July 26.
A reflection of planet
Earth's rotation on its axis, the concentric trails of these celestial
beacons along with
trails of stars
are punctuated at their ends by a separate final frame
in the morning skyview.
Easy to pick out, Venus is brightest and near the trees close to the
horizon.
Jupiter arcs above it, toward the center of the image along with
the compact Pleiades star cluster and V-shaped Hyades anchored by
bright star Aldebaran.
One trail looks wrong, though.
Not concentric with the others and so not a reflection of Earth's
rotation, the International Space Station streaks off the right
side of this scene, glinting in sunlight
as it orbits planet Earth.
APOD: 2012 June 3 - A Picturesque Venus Transit
Explanation:
The rare
transit of Venus across the face of the Sun in 2004 was one of the better-photographed events in sky history.
Both scientific and artistic images flooded in from the areas that could see
the transit: Europe and much of Asia, Africa, and North America.
Scientifically, solar photographers confirmed that the
black
drop effect is really better related to the viewing clarity of the camera or telescope than the atmosphere of Venus.
Artistically, images might be divided into several categories.
One type captures the
transit in front of a highly detailed Sun.
Another category captures a double coincidence such as both Venus and an airplane simultaneously silhouetted, or
Venus and the
International Space Station in low Earth orbit.
A third image type involves a fortuitous arrangement of interesting looking clouds, as shown by example in the
above image
taken from
North Carolina, USA.
Sky enthusiasts worldwide are abuzz about the coming transit of
Venus on Tuesday.
It is perhaps
interesting to wonder whether any person will live to see -- and remember seeing -- both Tuesday's Venus transit and the next one in 2117.
APOD: 2012 May 4 - Fermi Epicycles: The Vela Pulsar's Path
Explanation:
Exploring the cosmos at extreme energies, the
Fermi Gamma-ray Space Telescope
orbits planet Earth every 95 minutes.
By design,
it rocks to the north and then to the
south on alternate orbits in order to
survey the sky
with its Large Area Telescope (LAT).
The spacecraft also rolls so that
solar panels are kept pointed at the Sun for power,
and the axis of its
orbit precesses
like a top, making a complete rotation once every 54 days.
As a result of these multiple cycles
the paths of gamma-ray sources trace out
complex patterns from the spacecraft's perspective,
like this mesmerising plot of the path of the Vela Pulsar.
Centered on the LAT instrument's field of view, the plot spans 180
degrees and follows Vela's position
from August 2008 through August 2010.
The concentration near the center
shows that Vela was in the sensitive region
of the LAT field during much of that period.
Born in the death explosion
of a massive star within our
Milky Way galaxy,
the Vela Pulsar
is a neutron star spinning 11 times a second, seen
as the brightest persistent source in the gamma-ray sky.
APOD: 2011 December 31 - Comet Lovejoy and the ISS
Explanation:
On December 24,
Comet Lovejoy rose in dawn's twilight,
arcing above the eastern horizon, its tails
swept back
by the solar wind and sunlight.
Seen on the left
is the comet's
early
morning appearance
alongside the southern Milky Way from the town of Intendente Alvear,
La Pampa province, Argentina.
The short star trails include bright southern sky stars
Alpha and Beta Centauri near
the center of the frame, but the long bright streak that crosses the
comet tails is a little closer to home.
Waiting for
the proper moment to start his exposure,
the photographer has also caught the
International
Space Station still glinting
in the sunlight as
it orbits (top to bottom) above the local horizon.
The right panel
is the near horizon view of Comet Lovejoy
from the space station itself, captured only two days earlier.
In fact, Dan Burbank, Expedition 30 commander,
recorded Comet Lovejoy rising just before the Sun in a
spectacular video (linked here).
Even considering the
other vistas available from
low Earth orbit, Burbank describes the comet as
"the most amazing thing I have ever seen in space."
APOD: 2011 July 9 - Atlantis Reflection
Explanation:
Space shuttle orbiter
Atlantis left planet Earth
on Friday, July 8, embarking on the STS-135 mission
to the International Space Station.
The momentous launch was the final one
in NASA's 30 year
space shuttle program
that began with the launch of the first reusable spacecraft on
April 12, 1981.
In this reflective
prelaunch image from July 7,
Atlantis stands in
a familiar spot on the
Kennedy Space Center's pad 39A, after an early evening
roll back of the pad's Rotating Service Structure.
The historic orbital
voyages of Atlantis have included a
Hubble Space Telescope
servicing mission, deployment of
Magellan,
Galileo, and the
Compton Gamma-ray Observatory,
and seven trips to the Russian
space station Mir.
Scheduled to dock once again with the
International Space Station
on Sunday, Atlantis has now made its 33rd and final trip to orbit.
APOD: 2011 May 21 - Planets, Endeavour at Dawn
Explanation:
When dawn broke over Kennedy Space Center on Monday, May 16,
the space shuttle orbiter
Endeavour still stood on pad 39A.
Its final launch, on
mission STS-134 to the International Space
Station, was only hours away.
Shining through the early morning
twilight four planets
were also poised above the eastern horizon,
a moving scene captured here from across the Banana River
at the center's Saturn V VIP viewing site.
Scattered by planet Earth's dense atmosphere, floodlight beams play
over the launch pad,
glancing skyward toward the celestial beacons.
Jupiter is highest, near the top of the frame, but even the solar
sytem's ruling gas giant is outshone by brilliant Venus near picture
center.
Innermost planet Mercury is below Venus, to the right.
Below and left, Mars almost fades into the twilight glow.
The four planets
continue to hug the eastern horizon at dawn throughout the month,
while Endeavour
is now scheduled to make
its final approach to planet Earth on June 1.
APOD: 2011 April 12 - 50 Years Ago: Yuri's Planet
Explanation:
On April 12th, 1961, Soviet cosmonaut
Yuri
Alexseyevich Gagarin became the first human in space.
His remotely controlled
Vostok 1
spacecraft lofted him to an altitude of 200 miles and
carried him
once around planet Earth.
Commenting on the first
view from space
he reported, "The sky is very dark; the Earth is bluish.
Everything is seen very clearly".
His view could have resembled
this image taken in 2003 from the
International Space Station.
Alan Shepard, the first US astronaut,
would not be launched until almost a month later and then
on a comparatively short suborbital flight.
Born on March 9, 1934,
Gagarin
was a military pilot before being
chosen for the first group of cosmonauts in 1960.
As a result of his
historic flight he became an
international hero and legend.
Killed when his
MIG jet crashed during a training flight in 1968, Gagarin was given a hero's funeral,
his ashes interred in the
Kremlin Wall.
Twenty years later, on yet another April 12th, in 1981, NASA launched the
first space shuttle.
APOD: 2011 March 9 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
In a recently completed rendezvous, the
Space Shuttle orbiter
Discovery, in its
final flight, visited the ISS and added components that included the
Leonardo Multi Purpose Logistics Module.
The ISS and many of its modules and expansive solar panels are visible in
the above picture
taken by the Discovery Crew after leaving the
ISS
to return to Earth.
The world's foremost
space outpost can be seen developing over the past several years
by comparing the above image
to
other
past
images.
Also visible above are many
different types of modules and
supply ships.
Construction began on the ISS in 1998.
APOD: 2011 January 31 - Japan's Kounotori2 Supply Ship Approaches the Space Station
Explanation:
The care package from Earth had arrived.
Last week, Japan launched the robotic
Kounotori2 spacecraft to bring needed
supplies,
including food, to the
International Space Station (ISS).
Kountori2 launched
from Japan's
Tanegashima Space Center a little over a week ago reached the ISS in low Earth late last week.
Pictured above, Kountori2
approached
the ISS and was about to be
grabbed
by astronauts with the
Canadarm2 and attached to the
Harmony Module.
In the
above picture as seen through a window on the
ISS, the limb of the Earth is visible, including white clouds, blue water, and various tan colored landforms.
In addition to launches including humans, as many as ten
robotic spacecraft may be launched to the space station this year, potentially including spacecraft from
Russia,
Europe, Japan, and a private company
in the USA.
APOD: 2011 January 5 - Eclipsing the Sun
Explanation:
Skywatchers
throughout much of Europe, North Africa, and Central Asia,
were treated to the first eclipse of the new year on January 4, a
partial
eclipse of the Sun.
But traveling to the area around Muscat, capital city of Oman,
photographer Thierry Legault planned to simultaneously record
two eclipses on that date,
calculating from that position,
for a brief moment, both the Moon and the International Space
Station could be seen in
silhouette, crossing the Sun.
His sharp, 1/5000th second exposure
is shown here, capturing
planet Earth's
two largest satellites against the bright solar disk.
As the partial solar
eclipse unfolded,
the space station (above and left
of center) zipped across the scene in less than 1 second,
about 500 kilometers from the photographer's telescope and camera.
Of course, the Moon was 400 thousand kilometers away.
Complete with sunspots,
the Sun was 150 million kilometers distant.
APOD: 2010 November 4 - Night Lights
Explanation:
Constellations of lights sprawl across
this night scene, but they
don't belong in the skies of planet Earth.
Instead, the view looks down from the
International Space Station
as it passed over the United States along the northern
Gulf Coast on October 29.
A Russian Soyuz spacecraft is docked in
the foreground.
Behind its extended solar panels, some 360 kilometers below,
are the recognizable
city lights of New Orleans.
Looking east along the coast to the top of the frame finds Mobile,
Alabama while Houston city lights stand out to the west, toward the bottom.
North (left) of New Orleans, a line of lights tracing central US
highway I55 connects to Jackson, Mississippi and Memphis, Tennessee.
Of course,
the lights follow the population centers, but not everyone lives on
planet
Earth all the time these days.
November 2nd marked the
first decade of continuous human presence
in space on board the International Space Station.
APOD: 2010 June 23 - Sunset from the International Space Station
Explanation:
What are these strange color bands being seen from the International Space Station?
The Sun setting through Earth's atmosphere.
Pictured above, a sunset captured last month by the ISS's
Expedition 23
crew
shows in vivid detail many layers of the
Earth's thin atmosphere.
Part of the
Earth experiencing night
crosses the bottom of the image.
Above that,
appearing in deep orange and yellow, is the Earth's
troposphere,
which contains 80 percent of the atmosphere by mass and
almost all of the
clouds in the sky.
Above the troposphere, seen as a light blue band with white clouds, is the
stratosphere, part of the Earth's atmosphere where airplanes fly and some hardy bacteria float.
Above the stratosphere, visible as a darker blue bands, are higher and thinner
atmospheric levels that gradually fade away into the cold dark
vacuum of
outer space.
Sunset is not an uncommon
sight
for occupants of the
International Space Station,
because it can be seen as many as 16 times a day.
APOD: 2010 May 23 - Station and Shuttle Transit the Sun
Explanation:
That's no sunspot.
On the upper right of the above image of the Sun, the dark patches are actually the
International Space Station (ISS) and the
Space Shuttle Atlantis on mission
STS-132.
In the past, many
skygazers
have spotted the space station and space shuttles as bright
stars gliding through
twilight skies, still
glinting in the
sunlight while orbiting about 350 kilometers above the
Earth's surface.
But here, astrophotographer
Thierry Lagault
accurately computed the occurrence of a rarer opportunity to
record
the spacefaring combination
moving quickly
in silhouette across the solar disk.
He snapped the
above picture on last Sunday on May 16,
about 50 minutes before the shuttle docked with the space station.
Atlantis was recently
launched to the ISS for its last mission before being retired.
APOD: 2010 April 8 - Discovery's Cloud
Explanation:
The space shuttle orbiter Discovery
is now docked with the
International Space Station,
some 350 kilometers
above
planet Earth.
Last Monday, its
launch to orbit was a beautiful one as it
rose into clear,
predawn skies at 6:21am EDT
from Kennedy Space Center's pad 39A.
Looking east, this time exposure was taken shortly after lift off from a
marina about 13 miles west of the launch site
in Titusville, Florida.
It shows the dawn's emerging colors along the horizon, with wafting
rocket contrails at the upper right.
The bright streak surrounded by the remarkable, elongated, vapor cloud
near the center of the image is the actual track
of Discovery, arcing toward the horizon and its
orbital rendezvous.
APOD: 2010 March 3 - The International Space Station from Above
Explanation:
The International Space Station (ISS) is the largest human-made object
ever to orbit the Earth.
The ISS is so large that it can be seen drifting overhead with the unaided eye, and is
frequently
imaged
from
the
ground
in
picturesque
fashion.
Last month, the station was
visited again by
space shuttle,
which resupplied the station and added a
new module.
The ISS is currently operated by the Expedition 22 crew, now consisting five astronauts including two supplied by
USA's NASA, two by
Russia's RKA,
and one by
Japan's JAXA.
After departing the
ISS, the crew of the space shuttle Endeavour captured
the above spectacular vista of the orbiting
space city high above the clouds, waters, and lands of Earth.
Visible components include modules,
trusses, and expansive
solar arrays
that gather sunlight that is turned into needed
electricity.
APOD: 2010 February 27 - Dawn's Endeavour
Explanation:
On February 21st, the Space Shuttle Endeavour and the International
Space Station (ISS) flew through the sky near
dawn over Whitby, Ontario, Canada.
Along with star trails, both were captured in this single time exposure.
Glinting in sunlight 350 kilometers above the Earth,
Endeavour slightly
preceeded the ISS arcing over
the horizon.
But the brighter trail and the brighter flare
belongs to the space station just visited
by Endeavour.
Near the completion of the STS-130 mission,
hours later Endeavour made a
night landing
at Kennedy Space Center.
APOD: 2010 February 16 - Dark Shuttle Approaching
Explanation:
What's that approaching?
Astronauts on board the
International Space Station
first saw it far in the distance.
Soon it enlarged to become a
dark silhouette.
As it came even closer, the
silhouette appeared to be a spaceship.
Finally, at just past 11 pm
(CST) last Tuesday, the object, revealed to be the
Space Shuttle Endeavour, docked as expected with the
Earth-orbiting space station.
Pictured above, Endeavour was imaged near Earth's horizon as it approached, where several layers of the
Earth's atmosphere were visible.
Directly behind the shuttle is the
mesosphere, which appears blue.
The atmospheric layer that appears white is the
stratosphere,
while the orange layer is Earth's
Troposphere.
This shuttle mission, which began with a
dramatic night launch
and will continue into next week, has many tasks planned.
These tasks include the delivery of the
Tranquility Module which includes a
cupola bay window complex that may allow even better views of spaceships approaching and leaving the space station.
APOD: 2010 January 17 - Atlantis to Orbit
Explanation:
Birds
don't fly this high.
Airplanes don't go this fast.
The Statue of Liberty
weighs less.
No species
other than human can even comprehend what is going on,
nor could any human just a millennium ago.
The launch of a
rocket bound for space is an event that
inspires awe and challenges description.
Pictured above, the
Space Shuttle Atlantis lifted off to
visit the
International Space Station
during the early morning hours of 2001 July 12.
From a standing start, the two million kilogram
rocket ship left to circle the
Earth where the
outside air is too thin to breathe and where there is
little
noticeable onboard gravity.
Rockets bound for space are now
launched from somewhere on Earth
about once a week.
APOD: 2009 December 7 - The International Space Station Over the Horizon
Explanation:
This was home.
Just over a week ago, the
STS-129 crew of the
Space Shuttle
Atlantis undocked from the
International Space Station (ISS) and returned to Earth.
As the shuttle departed the space station, they took the
above image.
Visible on the ISS are numerous
modules, trusses, and long wing-like solar panels.
The space shuttle crew spent almost 12 days calling the space station home.
The shuttle crew
resupplied the space station and delivered valuable spare parts.
The ISS continues to be home for five astronauts of Expedition 21.
The ISS's crew
now includes astronauts representing
NASA, the
European Space Agency, the
Russian Federal Space Agency, and the
Canadian Space Agency.
APOD: 2009 November 30 - Bright Sun and Crescent Earth from the Space Station
Explanation:
This was just one more breathtaking view from the International Space Station.
The Sun, a crescent Earth, and the long arm of a solar panel were
all visible outside a window when the
Space Shuttle
Atlantis visited the orbiting outpost last week.
Reflections from the window and
hexagonal
lens flares
from the camera are superposed.
The space
shuttle landed Friday after a successful 10 day
mission
to expand and resupply the
ISS.
Numbered
STS-129,
the space shuttle mission returned astronaut
Nicole Stott
to Earth from her stay on the ISS as a
Flight Engineer in the
Expedition 20 and 21 crews.
APOD: 2009 October 22 - Moon and Planets in the Morning
Explanation:
Last Friday, a gathering of three bright planets and the Moon
graced the morning sky.
With Mercury, Venus, Saturn, and a narrow lunar crescent
close to the eastern horizon in the dawn twilight, this picture of
the beautiful conjunction
was recorded near Noerdlingen, Germany.
These planets are wandering apart now and
Mercury is sinking
closer toward the rising Sun.
But if you also scan the rest of the sky this week
you should be able to add Jupiter and Mars to your planet spotting list,
as Mars rises around midnight and Jupiter shines brightly
after sunset.
In fact, if you want a better view of Jupiter
than Galileo had,
you might check out the
2009 International Year of Astronomy
activities
and events during these next few
Galilean Nights
(October 22-24).
APOD: 2009 October 5 - The International Space Station Over Earth
Explanation:
After undocking, the space shuttle Discovery crew got a memorable view of the developing International Space Station (ISS).
Pictured orbiting high above Earth last month,
numerous solar panels, trusses, and science modules of the
ISS were visible.
The Discovery crew brought
mission specialist
Nicole Stott to the
ISS, and returned astronaut
Timothy Kopra
to Earth.
Among the many mission and expedition accomplishments of the Discovery crew included delivering and placing the
Fluids Integrated Rack and the
Materials Science Research Rack in the
Destiny module as well as the
Minus Eighty
Degree
Laboratory Freezer
in the
Kibo module.
Better known, however, was the delivery of the
COLBERT
treadmill for keeping astronauts fit.
Over this past week the
Soyuz TMA-16 spacecraft carrying three more
astronauts docked with the ISS as
Expedition 21 is set to begin.
The
next shuttle trip
to the ISS is currently scheduled for 2009 November 12.
APOD: 2009 June 25 - Sarychev Peak Volcano in Stereo
Explanation:
From 400 kilometers
above
planet Earth, the Expedition 20 Crew
onboard the International Space Station
(ISS) was able to witness a
remarkable event from a remarkable vantage point --
the June 12 eruption of the
Sarychev Peak Volcano.
The active volcano is located in Russia's
Kuril Island chain,
stretching to the northeast of Japan.
Emphasizing the orbital perspective, this stunning color
stereo view
was made by combining two
images from the ISS and is
intended to be viewed with
red/blue
glasses (red for the left eye).
Punching upwards into the atmosphere at an early stage of the eruption,
the volcanic plume features a brown column of ash topped with a smooth,
bubble-like, white cloud that is likely water condensation.
Below, a cloud of denser grey ash slides down the volcanic slope.
About 1.5 kilometers of the island coastline is visible at ground
level.
The evolving
ash plume posed no danger to the Expedition 20 crew,
but commercial airline flights were diverted away
from the region to minimize the danger of engine failures from ash intake.
APOD: 2009 June 13 - The Milky Road
Explanation:
Inspired by the night skies of planet Earth
in the International
Year of Astronomy,
photographer Larry Landolfi created this
tantalizing
fantasy view.
The composited image
suggests a luminous Milky Way is the heavenly extension of a country road.
Of course, the
name for our galaxy, the
Milky Way
(in Latin, Via Lactea), does refer to its appearance
as a milky band or path in the sky.
In fact, the word galaxy itself derives from the Greek for milk.
Visible on
moonless nights
from dark sky areas,
though not so bright or colorful as in this image, the glowing
celestial
band is due to the collective light of myriad stars along the
plane of our galaxy, too faint to be distinguished individually.
The diffuse starlight is cut by dark swaths of
obscuring galactic dust clouds.
Four hundred years ago, Galileo turned his
telescope on the Milky Way and announced it to be
"... a congeries of
innumerable
stars ..."
APOD: 2009 April 6 – The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
In a recently completed mission, the
Space Shuttle orbiter
Discovery visited the ISS and added components that included
a new truss and new solar panels.
The entire array of expansive solar panels is visible in
the above picture taken by the Discovery Crew after leaving the
ISS
to return to Earth.
The world's foremost
space outpost can be seen developing over the past several years
by comparing the above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, and a
supply ship.
Construction began on the ISS in 1998.
APOD: 2009 April 3 - Around the World in 80 Telescopes
Explanation:
Want to go on an extraordinary voyage?
Today you can, by watching
Around the
World in 80 Telescopes.
The 24-hour long webcast is organized by the European Southern
Observatory for the
International Year of Astronomy
cornerstone project 100 Hours of Astronomy.
As suggested in this astronomically intense composite,
the webcast event follows
night and day around the globe to visit some of the most
advanced observatories on Earth and in space,
exploring the universe in visible light and beyond.
The Gemini North Telescope
(Hawaii, USA) and the
large observatories at the summit of
volcanic Mauna Kea
are scheduled for the first stops in the program beginning April 3 at
09:00
UT.
Others on the schedule include the
Swift
Satellite and
Fermi
Gamma-ray Space Telescope,
the Himalayan
Chandra Telescope (Hanle, India), and
the 10-meter South Pole Telescope
and IceCube Neutrino Telescope
(South Pole, Antarctica).
APOD: 2009 April 2 - 100 Hours of Astronomy Begins
Explanation:
Today,
100 Hours of Astronomy
begins, a cornerstone project of the
International Year of Astronomy 2009
celebrating the 400th anniversary
of
Galileo's original telescopic
exploration of the sky.
Running from April 2 through April 5, many different public programs are
planned
worldwide
as part of the project, starting with today's
opening
event at the Franklin Institute in Philadelphia.
Featuring one of Galileo's two remaining telescopes, the event will be
webcast
live.
Of course, the sky
examined by Galileo can still be appreciated today,
with much more
capable instruments
that are widely available.
But
this skyward view
from a private
observatory in Veszprem, Hungary also
includes objects Galileo did not see when he
gazed into the night.
Recorded on March 26, the image captures the paired
trails of
the International Space Station (the brighter trail) and the shuttle orbiter
Discovery in low Earth orbit, as well as the streak of a passing airplane.
APOD: 2009 April 1 - Astronauts Head Upgraded During Spacewalk
Explanation:
First, a new truss was added.
Then, new solar panels were installed.
Now, as part of the
planned upgrade of the
International Space Station, an
Expedition 18
astronaut has upgraded her own head.
The Human Extended Analog Device 9000 was attached with only minor delays,
making the astronaut's remaining
spacewalks over 40 percent more efficient.
With the HEAD 9000 attached, an astronaut can now directly access 4 Gigabytes of computer flash memory with their
own brain, perform
complex mathematics by "directed thinking", and play a pre-installed game of
Tetris
at no additional charge.
Happy
April Fools' Day from
the folks at
APOD.
In reality, the space shuttle
Discovery's mission
to upgrade the International Space Station ended Saturday after upgrading only the space station.
The above image of astronaut
Heidemarie Stefanyshyn-Piper handling the box-like Nitrogen Tank Assembly was actually
taken last November.
For some reason, however, Astronaut Stefanyshyn-Piper can now factor 11 digit
prime numbers in her head.
APOD: 2009 March 18 - GLOBE at Night: Help Track Light Pollution
Explanation:
How many stars can you see? Through next week, the
GLOBE at Night project invites
people from all over the world
to go outside at night, look up, and see!
Specifically, people are invited to go out an hour after sunset and look for the
constellation Orion toward the west.
Rather than count
Orion's stars directly, however, the
GLOBE at Night
website has made things easier by providing several
star charts
to which you can compare your
view of Orion.
Possible matches extend from a
bright sky
where only a few Orion stars are visible, to a very
dark sky
where over 100 Orion stars are visible.
Pictured above
are results from
last year's sky observation campaign.
Since 2009 is the
International Year of Astronomy,
it is hoped that an even better map can be created this year.
By participating
in this easy and fun activity, you are helping
humanity to better
understand how
light
pollution
is changing across the Earth.
APOD: 2009 February 6 - Space Station in the Moon
Explanation:
On February 2nd,
a first quarter
Moon
shone in planet Earth's
early evening sky.
As seen from a location on the US west coast near
Mt. Hamilton,
California, the
International Space Station also arched above
the horizon, crossing in front of the Moon's sunlit surface.
The space station's transit
lasted 0.49 seconds.
This sharp exposure, a well-timed
telescopic image,
recorded the space station during the transit
against the background of the
Moon's smooth Mare Serenitatis
(Sea of Serenity).
The orbital outpost was
traveling northwest to southeast
(from 2 o'clock to 8 o'clock) at a range of
389 kilometers or about 230 miles.
Of course, the
Moon itself was
1,000 times farther away.
In the remarkable photo, the glinting station also offers
a hint of the bluish reflection
of earthlight.
APOD: 2009 January 1 - Welcome to the International Year of Astronomy
Explanation:
Astronomers all over planet Earth invite you to experience the night sky as part of the
International Year of Astronomy 2009.
This year was picked by the
International Astronomical Union
and the United Nations Educational, Scientific, and Cultural Organization
because it occurs 400 years after
Galileo
turned one of the first telescopes toward the heavens.
Peering through that small window,
Galileo discovered that the
Moon has craters,
Venus has phases,
Jupiter has moons,
and Saturn has rings.
This year you can discover these and many modern wonders of the amazing overhead tapestry that is shared by all of humanity.
If, like many others, you find the night sky
wondrous and educational, be sure to attend an
IYA2009 event in your area,
and tell any schools and children that might be interested.
Also, please feel free to explore the extensive
IYA2009 web pages to find international media events that include
blogs,
webcasts and
much
much
more.
APOD: 2008 December 31 - The Sky in Motion
Explanation:
Still need to come up with a good new year's resolution?
Consider one appropriate for 2009, the
International Year of Astronomy;
just look up -- experience, learn, and enjoy the changing sky.
This 4-minute, time-lapse video is
composed from a series of 7,000 images highlighting
much of what you could see.
Arcing through the sky in a stately reflection of
planet Earth's
own rotation are
Moon,
Sun and
stars.
But the sequence also features
satellites and
meteors streaking overhead,
clouds moving
along the horizon changing in a beautiful
iridescence, and beaming
crepuscular
rays.
APOD: 2008 December 2 - International Space Station: Find the Astronaut
Explanation:
Where's the astronaut?
Somewhere in this impressive array of
International Space Station (ISS) hardware, astronaut
Steve Bowen can be found upgrading and cleaning key parts of
Earth's most prominent orbital outpost.
Astronaut Bowen and
Heidemarie Stefanyshyn-Piper (not pictured), part of the
Space Shuttle Endeavour's recently ended STS-126 mission to the ISS,
spent nearly three hours on this spacewalk
hovering high above planet Earth.
Bowen progressed toward achieving a key goal of
the mission --
servicing of the Solar Alpha Rotary Joints to better allow some solar arrays to track the Sun.
In the lower foreground of the
above image is the cylindrical
Columbus Laboratory,
protruding from the right is an impressively large
space station truss, while in the background are some of the expansive solar arrays that collect sunlight to power the
ISS.
Far in the distance, a blue arc of
Earth's thin atmosphere is visible on the horizon.
The next space shuttle flight is
scheduled for 2009 February, when
Discovery
will deliver elements to further
expand the ISS.
APOD: 2008 November 20 - Endeavour in the Moon
Explanation:
Glaring near the top of the frame, the shuttle orbiter Endeavour
rockets
into the night on the
STS-126 mission.
Endeavour
left planet Earth on November 14 from
Launch Pad 39A at
NASA's Kennedy Space Center, making the 27th flight to the
International Space Station.
To record the dramatic view, the camera was placed so the shuttle's flight
path tracked across the Moon, from a vantage point in
Indian River City, Florida.
Near picture center the almost full,
perigee Moon shining through
thin clouds silhouettes the shuttle's dense exhaust trail.
On board the space station, the crew and the STS-126 astronauts
can celebrate the orbital outpost's
10th anniversary today.
Construction of
the International Space Station officially began
with the November 20, 1998 Russian launch of the station's first
element, the bus-sized Zarya module.
APOD: 2008 November 13 - A Bubble in Cygnus
Explanation:
Adrift in the
rich star fields
of the constellation Cygnus, this
lovely, symmetric bubble nebula was only recently recognized and may
not yet appear in astronomical catalogs.
In fact, amateur astronomer
Dave Jurasevich identified
it as a nebula on July 6 in
his
images of the complex
Cygnus region that included the Crescent Nebula (NGC 6888).
He subsequently notified the International Astronomical Union.
Only eleven days later the same object was independently identified by
Mel Helm at Sierra Remote
Observatories,
imaged by Keith Quattrocchi and Helm, and also submitted to the IAU
as a potentially unknown nebula.
Their final composite image is seen here,
including narrow-band image data that highlights the
nebula's delicate outlines.
What is the newly recognized bubble nebula?
Like the Crescent Nebula
itself, this cosmic bubble could be blown by
winds from a massive
Wolf-Rayet star, or it could be a
spherically-shaped planetary nebula,
a final phase in the life of a sun-like star.
APOD: 2008 October 17 - An Extraordinary Voyage
Explanation:
Nineteenth century science fiction author
Jules Verne
wrote visionary works about
Extraordinary
Voyages including tales of space flight and the story of a journey
From the Earth
to the Moon.
Fittingly, the European Space Agency's newly developed
Automated Transfer Vehicle
(ATV), a robotic spacecraft
intended to deliver cargo to the International Space Station
(ISS)
was named in his honor and successfully docked
with the ISS earlier this year.
When the
Jules Verne ATV
was undocked and deorbited last month,
its safely controlled reentry over the Pacific Ocean
was followed by astronomers in order to make detailed comparisons
of the actual event with computer models of spacecraft
reentry and breakup in the atmosphere.
This dramatic
image of the fragmenting,
13-ton spacecraft is a high definition video frame recorded from
NASA's DC-8 Airborne Laboratory.
The observations were part of the joint ESA/NASA
Jules Verne Multi-Instrument
Aircraft Campaign.
APOD: 2008 October 16 - 48 Years of Space Flight
Explanation:
This year, NASA celebrated its
50th anniversary.
Inspired to make his own contribution,
astronomer Ralf Vandebergh set out to record images
of some historic spacecraft in Earth orbit --
captured with his own modest equipment and a hand-guided,
10-inch, Newtonian reflecting telescope.
One result is this intriguing composite effectively
spanning 48 years of space flight!
From a 1960 launch, on the left is the
TIROS 2
satellite, one of the first successful
weather satellites.
While this TIROS
(Television InfraRed Observation System) satellite
stopped functioning in 1961,
Vandebergh notes that if we could visit it now, we would
still find
video cameras and magnetic tape recorders.
On the right, of course, is the ISS
(International Space Station)
including its recent addition, the
Progress M-65 cargo vehicle,
launched to the ISS just last month.
APOD: 2008 August 30 - The View from Everest
Explanation:
What would it be like to stand
atop
the tallest mountain on Earth?
To see a full panoramic vista from there, scroll right.
Visible are snow peaked mountains near and far,
tremendous cliffs, distant plateaus,
the tops of clouds, and a dark blue sky.
Mt. Everest stands 8.85 kilometers above sea level,
roughly the maximum height reached by international
airplane flights,
but much less than the 300 kilometers achieved by a
space shuttle.
Hundreds of people have tried and failed to climb the
behemoth by foot, a feat
first
accomplished successfully in 1953.
About 1000 people have now
made it to the summit.
Roddy Mackenzie, who climbed the mountain in 1989, captured the
above image.
Mt. Everest lies in the
Himalaya mountains in the country of
Nepal.
In the
native language of Nepal,
the mountain's name is "Sagarmatha" which
means "forehead of the sky."
APOD: 2008 August 28 - Fermi's First Light
Explanation:
Launched
on June 11 to explore the universe at extreme energies,
the Gamma-ray Large Area Space Telescope has been
officially renamed the
Fermi Gamma-ray Space Telescope, in
honor of Nobel Laureate
Enrico Fermi (1901-1954), pioneer
in high-energy physics.
After testing, Fermi's
two instruments,
the Gamma-ray Burst Monitor (GBM) and the Large Area Telescope (LAT),
are now regularly returning data.
Fermi's first map of the
gamma-ray
sky from the LAT is shown in this false-color image, an
all-sky view that looks toward the center of our
Milky Way Galaxy
with the galactic plane projected across the middle.
What shines in the gamma-ray sky?
Along the galactic plane, energetic cosmic rays collide with gas
and dust to produce the diffuse gamma-ray glow.
Strong emission from spinning neutron stars or
pulsars,
and distant
active
galaxies known as blazars, can be identified by
placing your cursor over the map.
A prelude
to future discoveries,
the remarkable result combines only 4 days of observations,
equivalent to a year of observations with the
Compton
Gamma-ray Observatory mission of the 1990s.
In addition to the ability to monitor
gamma-ray bursts,
the greatly improved sensitivity will allow Fermi to look deeper
into the high-energy Universe.
APOD: 2008 July 30 - The International Space Station Transits the Sun
Explanation:
That's no sunspot.
It's the
International Space Station (ISS)
caught by chance passing in front of the Sun.
Sunspots, individually, have a dark central
umbra, a lighter surrounding penumbra,
and no solar panels.
By contrast, the ISS is a complex and multi-spired mechanism,
one of the largest and most sophisticated machines ever created by
humanity.
Also, sunspots occur on the
Sun, whereas the ISS orbits the
Earth.
Transiting the Sun is not very unusual for the
ISS, which orbits the Earth about every 90 minutes,
but getting one's timing and equipment just right for a
great image is rare.
Strangely, besides that fake spot, the Sun, last week,
lacked any real sunspots.
Sunspots have been
rare
on the Sun since the dawn of the current
Solar Minimum,
a period of low solar activity.
Although fewer sunspots have been
recorded during this
Solar Minimum
than for
many previous decades, the low solar activity is
not, as yet, very unusual.
APOD: 2008 July 13 - A Dark Sky Over Death Valley
Explanation:
This eerie glow over Death Valley is in danger.
Scrolling right will show a spectacular view from one of the
darkest places left in the continental
USA:
Death Valley,
California.
The above 360-degree full-sky panorama is a composite of 30 images taken two years ago in
Racetrack Playa.
The image has been digitally processed and increasingly stretched at high altitudes to make it rectangular.
In the foreground on the image right is an
unusually placed rock
that was pushed by high winds onto
Racetrack Playa
after a slick rain.
In the background is a
majestic night sky,
featuring thousands of stars and many constellations.
The arch across the middle is the central
band of our
Milky Way Galaxy.
Light pollution
is threatening dark skies like this all
across the US and the world, and therefore the
International Dark-Sky Association and the
US National Parks Service are
suggesting methods that can
protect
them.
APOD: 2008 June 23 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
Earlier this month, the
Space Shuttle orbiter
Discovery visited the ISS and added components that included
Japan's
Kibo Science Laboratory.
The entire array of expansive solar panels is visible in
this picture taken by the Discovery Crew after leaving the
ISS
to return to Earth.
The world's foremost
space outpost can be seen developing over the past several years
by comparing the above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, another impressive set of
solar panels, and a supply ship.
Construction began on the ISS in 1998.
APOD: 2008 May 14 - A Supply Ship Docks with the International Space Station
Explanation:
Looking out a window of the International Space Station brings breathtaking views.
Visible vistas include a vast and
colorful Earth, a
deep dark sky, and an occasional
spaceship sent to visit the station.
Visible early last month was a
Soyuz
TMA-12 spacecraft carrying not only supplies but also three newcomers.
The three new astronauts were
Expedition 17 commander Sergei Volkov,
flight engineer Oleg Kononenko, and spaceflight participant
So-yeon Yi.
Yi returned to Earth
a few days later, while Volkov and Konenenko are scheduled to return in a few months.
The docking module
pictured above involved the
Pirs
Docking Compartment.
The Expedition 17 crew, including NASA flight engineer
Gregory
Chamitoff, will carry out repairs on the
ISS, explore new methods of living in space,
and conduct research in space including the effects of
space radiation on
vitamin molecules.
APOD: 2008 March 16 - Endeavour to Orbit
Explanation:
Birds
don't fly as high.
Airplanes don't go as fast.
The Statue of Liberty
weighs less.
No species
other than human can even comprehend what is going on,
nor could any human just a millennium ago.
The launch of a
rocket bound for space is an event that
inspires awe and challenges description.
The
exhaust column
pictured is from the
Space Shuttle Endeavour after
last week's night launch to visit the
International Space Station.
Endeavour's rocket engines create the dramatic glow from above
the clouds.
From a standing start, the two million kilogram
rocket ship left to circle the
Earth where the
outside air is too thin to breathe and where there is
little
noticeable onboard gravity.
Rockets bound for space are now
launched from somewhere on Earth
about once a week.
APOD: 2008 March 14 - Endeavour into the Night
Explanation:
Blasting into a dark night sky, the Space Shuttle Endeavour began
its latest journey to orbit in the early morning hours of March 11.
In this stunning picture following the launch,
the glare
from Endeavour's three
main rocket engines and flanking solid fuel
booster rockets illuminates the
orbiter's tail section and
the large, orange external
fuel tank.
Embarking on mission
STS-123, Endeavour left Kennedy Space Center's
pad 39A, ferrying a crew of seven
astronauts to the International Space Station
(ISS).
The cargo included the first section of the Japan Aerospace Exploration
Agency's Kibo laboratory and the Canadian Space Agency's two-armed
robotic system.
Astronauts will conduct a series of
space walks to install the new equipment during the
16-day mission, the longest shuttle mission to the ISS.
APOD: 2008 March 5 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
Last month, the
Space Shuttle orbiter
Atlantis visited the
ISS and added components that included the
Columbus Science Laboratory.
The entire array of expansive solar panels is visible in
this picture taken by
the Atlantis Crew after
leaving the
ISS
to return to Earth.
The world's foremost
space outpost can be seen developing over the past several years
by comparing the
above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, another impressive set of
solar panels, and a supply ship.
Construction began on the ISS in 1998.
APOD: 2008 February 28 - ISS: Sunlight to Shadow
Explanation:
Orbiting 400,000 kilometers above the Earth, the
Moon slid
into Earth's shadow to begin last week's total lunar
eclipse.
Of course the
International Space Station (ISS) slides into
Earth's shadow every 90 minutes, the time it takes it to complete one
orbit at
an altitude of about 400 kilometers.
Recorded near sunset on February 7,
looking toward the north,
this
composite of 70 exposures shows the trail of the
ISS (with gaps between exposures) as it moved left to right
over the city of Tübingen in southern Germany.
Beginning
in sunlight on the left, the ISS vanishes as it enters
Earth's shadow at the far right, above the northeastern horizon.
As seen from Tübingen, the passage took about 4 minutes.
Clicking on the image will download a
time-lapse animation
(mpg file) based on the individual exposures that includes a plane flying
along
the horizon.
APOD: 2008 February 19 - Columbus Laboratory Installed on Space Station
Explanation:
The International Space Station (ISS) has been equipped with a powerful new scientific laboratory.
The Space Shuttle Atlantis delivered the
Columbus Laboratory
to the ISS
and installed the seven meter long module over the past week.
Columbus
has ten racks for experiments that can be controlled from the station or the
Columbus Control Center
in Germany.
The first set of experiments includes the
Fluid Science Laboratory
that will explore fluid properties in the
microgravity
of low Earth orbit, and
Biolab which supports experiments on
microorganisms.
Future Columbus experiments include an
atomic clock that will test
minuscule timing effects including those expected by
Einstein's
General Theory of Relativity.
Pictured above, mission specialist
Hans Schlegel
works on the outside of Columbus.
Scientists from all over the world
may propose and carry out experiments to be done on the laboratory during its ten year mission.
APOD: 2008 January 13 - Hurricane Ivan from the Space Station
Explanation:
Ninety percent of the houses on
Grenada were
damaged by the destructive force of
Hurricane Ivan.
At its peak,
Ivan was a
Category 5 hurricane,
the highest power category on the
Saffir-Simpson Scale,
and created sustained
winds
in excess of 200 kilometers per hour.
Ivan was the largest
hurricane to strike the US in 2004, and,
so far, the 10th most powerful in recorded history.
As it swirled in the
Atlantic Ocean,
the tremendous
eye of Hurricane Ivan was
photographed from above by the orbiting
International Space Station.
The name Ivan has now been retired from Atlantic Ocean use by the
World Meteorological Organization.
APOD: 2007 December 27 - Earth at Twilight
Explanation:
No sudden, sharp boundary marks the passage of day
into night in
this gorgeous view
of ocean and clouds over our
fair
planet Earth.
Instead, the shadow line or
terminator is
diffuse and shows
the gradual transition to darkness we experience as twilight.
With the Sun illuminating the scene from the right,
the cloud tops reflect gently reddened
sunlight
filtered
through the dusty troposphere, the lowest layer of the planet's
nurturing
atmosphere.
A clear high altitude layer,
visible along the dayside's upper edge,
scatters blue
sunlight and fades into the blackness of space.
This picture
actually is a single digital
photograph taken in June
of 2001 from the International Space Station
orbiting at an
altitude of 211
nautical
miles.
APOD: 2007 November 8 - VERITAS and Venus
Explanation:
Early morning risers and late to bed astronomers have recently
enjoyed
bright planets in predawn skies, with
brilliant Venus above the eastern horizon.
On November 5, Venus was joined by the waning crescent
Moon.
This self-portrait by astronomer Larry Ciupik captures the
lovely pairing of the two brightest celestial beacons on the scene,
though the Moon, right of Venus, is strongly over exposed.
Included at the far left in the 30 second exposure is the bright
streak of the International
Space Station still docked with shuttle orbiter
Discovery.
Together in Earth orbit, the
spacefaring combination was momentarily
the third brightest
sky
light in view.
In dim silhouette, a multi-mirrored unit of the
Very Energetic Radiation Imaging Telescope Array System
(VERITAS)
is also visible in the foreground.
VERITAS operates at the Whipple Observatory near Tucson, Arizona
to detect high-energy gamma-rays
from the cosmos.
APOD: 2007 September 29 - Dawn Launch Mosaic
Explanation:
Shortly
after sunrise on Thursday at
Cape Canaveral
Air Force Station, the
Dawn
spacecraft began its journey to the asteroid belt,
arcing eastward into a blue and cloudy sky.
Dawn's voyage began on a conventional,
chemically
fueled Delta II
rocket, but will continue with an
innovative
ion propulsion system.
The spacecraft's extremely
efficient
ion engines will use electricity
derived from solar power to ionize xenon atoms and generate
a gentle but continuous thrust.
After a four year interplanetary cruise, Dawn will orbit
two small worlds, first Vesta and then Ceres.
Vesta is one of the largest main belt asteroids, while nomenclature
introduced by the International Astronomical Union in 2006 classifies
nearly spherical Ceres as a dwarf planet.
APOD: 2007 June 25 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
During the past week, the
Space Shuttle
Atlantis visited the
ISS and added pieces of the
Integrated Truss Structure that mirrored those added in September 2006, including a second
impressively long
array of solar panels.
The entire array of expansive solar panels are visible at the edges of the
above image taken by the
Shuttle Atlantis Crew after leaving the
ISS to return to Earth.
The world's foremost space outpost
can be seen developing over the past several years by comparing the
above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, another impressive set of
solar panels, and a supply ship.
Construction began on the
ISS in 1998.
APOD: 2007 June 22 - Small Worlds Ceres and Vesta
Explanation:
Ceres and
Vesta are, respectively, only
around 950 kilometers and 530 kilometers in diameter - about
the size of Texas and Arizona.
But they are two of the largest of over 100,000
minor bodies
orbiting in the main asteroid belt between Mars and Jupiter.
These remarkably detailed
Hubble Space Telescope images
show brightness and color variations
across the surface of the two small worlds.
The variations could represent large scale
surface features or areas of different compositon.
The Hubble image data will help astronomers plan for a
visit by the asteroid-hopping
Dawn spacecraft,
scheduled for launch on July 7 and intended to orbit first
Vesta and then
Ceres after a four year interplanetary cruise.
Though
Shakespeare might not have been impressed,
nomenclature introduced by the International Astronomical
Union in 2006 classifies nearly spherical Ceres as a
dwarf planet.
APOD: 2007 June 12 - Shuttle Plume
Explanation:
What kind of cloud is that? Not a naturally occurring one.
Pictured above
is the drifting smoke plume left over from last Friday's launch of the
Space Shuttle Atlantis.
The twisted plume was captured shortly after launch high above NASA's massive
Vehicle Assembly Building, the largest single story building in the world.
Rockets frequently create
picturesque plumes during launch.
The Space Shuttle is currently visiting the
International Space Station
and delivering a new backbone truss segment to the continually developing and
occupied spaceport.
This trip, officially labeled
STS-117, is the 118th space shuttle
flight overall and the 28th for the Atlantis Orbiter.
APOD: 2007 May 8 - A Dark Sky over Death Valley
Explanation:
This eerie glow over Death Valley is in danger.
Scrolling right will show a spectacular view from one of the
darkest places
left in the continental
USA:
Death Valley,
California.
The above 360-degree full-sky panorama is a composite of 30 images taken two years ago in
Racetrack Playa.
The image has been digitally processed and increasingly stretched at high altitudes to make it rectangular.
In the foreground on the image right is an
unusually placed rock
that was pushed by high winds onto
Racetrack Playa
after a slick rain.
In the background is a majestic night sky, featuring thousands of stars and many constellations.
The arch across the middle is the central
band of our
Milky Way Galaxy.
Light pollution
is threatening dark skies like this all
across the US, and therefore the
International Dark-Sky Association and the
US National Parks Service are
suggesting methods that can
protect
them.
APOD: 2007 April 23 - A Supply Ship Approaches the Space Station
Explanation:
Looking out a window of the
International Space Station
brings breathtaking views.
Visible vistas include a vast and colorful Earth, a deep dark sky,
and an occasional spaceship sent to visit the station.
Visible on September 20 of last year was a
Soyuz TMA-9 spacecraft
carrying not only supplies but also three new astronauts.
A few days before
this picture was taken, the U.S.
Space Shuttle Atlantis
had just departed.
The three new approaching astronauts were American Michael E. Lopez-Alegria, Russian Mikhail Tyurin, and Iranian-American
Anousheh Ansari.
Ms. Ansari visited the International Space Station (ISS)
briefly as a paying spaceflight participant for the
Federal Space Agency
of Russia, and wrote a
popular blog about her experiences.
Lopez-Alegria would lead the ISS crew dubbed
Expedition 14, which included the flight engineer and Soyuz pilot Tyurin,
flight engineer American Sunita Williams, and flight engineer German
Thomas Reiter.
Tyurin returned to the Earth with Lopez-Alegria this past week.
APOD: 2007 April 8 - The View from Everest
Explanation:
What would it be like to stand
atop
the tallest mountain on Earth?
To see a full panoramic vista from there, scroll right.
Visible are snow peaked mountains near and far,
tremendous cliffs, distant plateaus,
the tops of clouds, and a dark blue sky.
Mt. Everest stands 8.85 kilometers above sea level,
roughly the maximum height reached by international
airplane flights,
but much less than the 300 kilometers achieved by a
space shuttle.
Hundreds of people have tried and failed to climb the
behemoth by foot, a feat
first
accomplished successfully in 1953.
About 1000 people have now
made it to the summit.
Roddy Mackenzie, who climbed the mountain in 1989, captured the
above image.
Mt. Everest lies in the
Himalayan mountains in the country of
Nepal.
In the
native language of Nepal,
the mountain's name is "Sagarmatha" which
means "forehead of the sky."
APOD: 2007 April 1- Americans Defeat Russians in First Space Quidditch Match
Explanation:
A historic first Space
Quidditch match came to a
spectacular conclusion last night as astronaut
Michael Lopez-Alegria caught the
Golden Snitch to give the Americans a hard fought victory over the Russians.
"The Russians used brilliant strategy, but only
NASA
had the T2KQMU (Thunderbolt 2000 Quidditch Maneuvering Unit)," commented
Lopez-Alegria, pictured above squeezing the elusive
Golden Snitch in his left hand.
Happy
April Fools Day
from the folks at
APOD.
In reality, Astronauts
Jeff Wisoff and Lopez-Alegria are
shown space-walking in 2001 October during a
space shuttle mission to help build the
International Space Station.
APOD: 2007 March 20 - A Blue Crescent Moon from Space
Explanation:
What's happening to the Moon?
Drifting around the Earth in 2006 July, astronauts from the
International Space Station (ISS) captured a
crescent Moon floating far beyond the horizon.
The captured above image is interesting because part of the
Moon appears blue,
and because part of the moon appears missing.
Both effects are created by the
Earth's atmosphere.
Air molecules
more efficiently scatter increasingly blue light, making the clear
day sky blue for ground observers, and the horizon blue for astronauts.
Besides reflecting sunlight, these
atmospheric molecules
also deflect moonlight, making the lower part of the moon appear to fade away.
As one looks higher in the
photograph, the increasingly thin atmosphere appears to
fade to black.
APOD: 2006 December 25 - Upgrading the International Space Station
Explanation:
The International Space Station (ISS) will be the largest
human-made object ever to
orbit the
Earth.
The station is so large that it could not be
launched all at once --
it is being built piecemeal with large sections added
continually by flights of the
Space Shuttle.
To function, the ISS needs
trusses to keep it rigid and to route
electricity and liquid coolants.
These
trusses are huge, extending over 15 meters long,
and with masses over 10,000 kilograms.
Pictured above earlier this month,
astronauts
Robert L. Curbeam (USA) and
Christer Fuglesang (Sweden) work to attach a new truss segment to the ISS and begin to upgrade the power grid.
APOD: 2006 October 14 - Full Moon Crossing
Explanation:
On October 6th, a nearly full
perigee Moon shone in
Earth's night sky.
The bright moonlight, accurate planning,
and proper equipment
resulted in
this amazing
composite featuring sharp
silhouettes of the International Space Station (ISS) as it
rapidly crossed (right to left)
in front of the lunar disk.
The picture was constructed using six video frames recorded
from a site just outside Tracy, California, USA.
Sporting newly deployed solar arrays,
the ISS was at a range
of about 260 miles from the telescope/video camera setup.
In the background, about a thousand times more distant than
the ISS, lies bright lunar ray crater
Tycho.
APOD: 2006 September 20 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its appearance again.
Over the past few days, the
Space Shuttle
Atlantis visited the
ISS and added pieces of the
Integrated Truss Structure, including an
impressively long
array of solar panels.
These expansive solar panels are visible extending from the lower right of the
above image taken by the
Shuttle Atlantis Crew after leaving the
ISS to return to Earth.
The world's foremost space outpost
can be seen developing over the past several years by comparing the
above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, another impressive set of
solar panels, and a supply ship.
Construction began on the
ISS in 1998.
APOD: 2006 September 16 - Discovery Orbiter Anaglyph
Explanation:
Approaching
the International Space Station on STS-121
in July,
the Shuttle Orbiter Discovery posed for a series of photographs.
The process was part of an inspection to check for damage
to the orbiter,
but against the backdrop of
planet Earth 300 kilometers below,
the pictures themselves are stunning.
Stereo artist Patrick Vantuyne has combined two of them
(ISS013e48787 and
ISS013e48788)
to produce this dramatic 3D image.
The stereo
anaglyph is intended to be viewed with red/blue glasses.
Details
visible along the forward fuselage include
high temperature (black) and low temperature (white)
insulation tiles,
thrusters used for steering and attitude
control, and crew compartment windows.
APOD: 2006 August 28 - Eight Planets and New Solar System Designations
Explanation:
How many planets are in the Solar System?
This popular question now has a new formal answer according the
International Astronomical Union (IAU): eight.
Last week, the IAU voted on a
new definition for planet and
Pluto did not make the cut.
Rather, Pluto was re-classified as a
dwarf planet and is considered as a prototype for a new category of
trans-Neptunian objects.
The eight planets now recognized by the IAU are:
Mercury,
Venus,
Earth,
Mars,
Jupiter,
Saturn,
Uranus, and
Neptune.
Solar System objects now classified as dwarf planets are:
Ceres,
Pluto, and the currently unnamed
2003 UB313.
Planets, by the new IAU definition, must be in orbit around the sun, be nearly spherical,
and must have cleared the neighborhood around their orbits.
The demotion of
Pluto to dwarf planet
status is a source of continuing
dissent and controversy in the astronomical community.
APOD: 2006 July 24 - The International Space Station on the Horizon
Explanation:
This was home.
Last week, the
STS-121 crew of the
Space Shuttle
Discovery undocked from the
International Space Station (ISS) and returned to Earth.
As the shuttle departed the space station, they took the
above image.
Visible on the ISS are numerous
modules, trusses, and long wing-like solar panels.
The space shuttle crew spent over 12 days calling the space station home.
The shuttle crew
resupplied the space station and prepared it for future assembly.
The ISS's crew
of two was expanded to three by the
shuttle visit, and now includes
one Russian,
one American, and
one European.
APOD: 2006 July 19 - Reflections on Planet Earth
Explanation:
Catching sight of
your reflection in
a store window or shiny hubcap can be
entertaining and occasionally even inspire a thoughtful moment.
So consider this reflective view
from 300 kilometers above planet Earth.
The picture is actually a self-portrait
taken by astronaut
Michael Fossum on July 8 during a space walk or extravehicular
activity while the
Discovery orbiter was docked with the
International Space Station.
Turning his camera to snap a picture of his own helmet visor,
he also recorded the reflection of his fellow
mission specialist,
Piers Sellers, near picture center and one of the space station's
gold-tinted solar power arrays arcing across the top.
Of course, the horizon of
our
fair planet lies in background.
APOD: 2006 July 8 - Discovery in Motion
Explanation:
On July 4th, the space shuttle orbiter Discovery rocketed into space on
mission STS-121.
Now docked with the International Space Station, Discovery
orbits
planet Earth at about 27 thousand kilometers per hour.
But in this dramatic sunset view
taken in May, Discovery is approaching the service structures
at Kennedy Space Center's launch pad 39B at the blinding speed of
(less than) 2 kilometers per hour.
Of course, the
orbiter,
booster rockets, and
external fuel tank
ride on one of NASA's workhorse crawler transporters.
Built for the Apollo program to carry the giant
Saturn V rocket, the
crawler transporters have seen four decades
of service.
APOD: 2006 June 7 - An Alaskan Volcano Erupts
Explanation:
What is happening to that volcano?
It's erupting!
The first person to note that the Aleutian
Cleveland Volcano
was spewing ash was astronaut Jeffrey N. Williams aboard the
International Space Station.
Looking down on the
Alaskan
Aleutian Islands
two weeks ago,
Williams noted,
photographed, and reported a spectacular
ash
plume emanating from the Cleveland Volcano.
Starting just before
this image was taken, the
Cleveland Volcano underwent a
short eruption lasting only about two hours.
The Cleveland
stratovolcano is one of the most active in the
Aleutian Island chain.
The volcano is fueled by
magma displaced by the
subduction
of the northwest-moving
tectonic
Pacific Plate
under the tectonic
North America Plate.
APOD: 2006 May 16 - The International Space Station from Above
Explanation:
The International Space Station (ISS) is the largest
human-made object ever to orbit the Earth.
Last August, the station was
visited and
resupplied by space shuttle
Discovery.
The ISS is currently operated by the Expedition 13 crew, consisting a Russian and an American astronaut.
After departing the
ISS, the crew of Discovery captured
this spectacular vista of the orbiting
space city high above the
Caspian Sea.
Visible components include modules,
trusses, and expansive
solar arrays
that gather sunlight that is turned into needed
electricity.
APOD: 2006 February 20 - SuitSat1: A Spacesuit Floats Free
Explanation:
Who dunnit?
Like a scene from a
space mystery movie, a spacesuit floated away from the
International Space Station earlier this month,
but no investigation was needed.
It was pushed out by the space station crew.
Dubbed
Suitsat-1, the unneeded Russian
Orlan spacesuit filled mostly with
old clothes
was fitted with a faint
radio transmitter
and released to orbit the Earth.
Suitsat-1 will orbit once every 90 minutes
until it burns up in the Earth's atmosphere within a few weeks.
The suit circled the Earth twice before its
radio signal became unexpectedly weak.
Pictured above, the lifeless spacesuit was photographed as it
drifted away from the Earth-orbiting
space station
earlier this month.
APOD: 2006 February 7 - UB313: Larger than Pluto
Explanation:
What do you call an outer Solar System object that is larger than Pluto?
Nobody is yet sure.
The question arose recently when
2003 UB313,
an object currently twice as far out as Pluto and not in the
plane with the rest of the planets, was
verified recently
to be 30 percent wider than
Pluto.
UB313's size was measured by a noting its distance from the
Sun and how much
infrared light it emits.
Previous size estimates were based only on visible light and greatly
affected by how reflective the object is.
Whether 2003 UB313
is officially declared a planet will be answered shortly by the
International Astronomical Union.
In the above picture, a scientific artist has imagined
UB313 in its
distant orbit around the Sun coupled with a hypothetical moon.
APOD: 2005 November 5 - Aurora from Space
Explanation:
From the ground,
spectacular
auroras seem to dance high above.
But the International Space Station
(ISS) orbits at nearly the same height
as many auroras, sometimes
passing over them, and
sometimes right through them.
Still, the auroral
electron and
proton
streams pose no direct danger to the
ISS.
In 2003, ISS Science Officer
Don
Pettit captured the green aurora,
pictured above in a digitally sharpened image.
From orbit,
Pettit reported that changing
auroras
appeared to crawl around like giant green
amoebas.
Over 300 kilometers below, the
Manicouagan Impact Crater can be seen in northern
Canada, planet Earth.
APOD: 2005 November 1 - A Soyuz Spacecraft Approaches the Space Station
Explanation:
Last month, a Soyuz TMA-7 spacecraft docked with the International Space Station.
The spacecraft was
launched a few days earlier from the
Baikonur Cosmodrome
in Kazakhstan.
Pictured above, the approaching
Soyuz spacecraft
carried the new
Expedition 12 crew to the Earth-orbiting
International Space Station (ISS), as well as
fee-paying spaceflight participant.
The Expedition 12 crew is expected to stay on the ISS for about six months,
while replacing the
Expedition 11 crew who had been on the station for about six months themselves.
About a week after this image was taken, the
Expedition 11 crew returned to Earth in the Soyuz capsule, along with the
spaceflight participant.
The Expedition 12 crew will carry out repairs on the
ISS, explore new methods of living in space, and conduct
research in space including a
kidney stone
experiment.
APOD: 2005 October 9 - Rollout of Soyuz TMA 2 Aboard an R7 Rocket
Explanation:
It takes a big rocket to go into space.
In 2003 April, this
huge Russian rocket
was launched toward Earth-orbiting
International Space Station (ISS),
carrying two astronauts who will make up the new Expedition 7 crew.
Seen here during rollout at the Baikonur Cosmodrome, the rocket's white top is actually the
Soyuz TMA-2, the most recent version of the
longest serving type of human spacecraft.
The base is a
Russian
R7 rocket, originally developed as a prototype
Intercontinental Ballistic Missile in 1957.
The
rocket spans the width of a football field and
has a fueled mass of about half a million kilograms.
Russian rockets like this remain a primary transportation system to the
International Space Station (ISS).
Last week, a similar rocket
successfully launched a
spaceflight participant
and two
Expedition 12 astronauts to the space station.
APOD: 2005 August 27 - 3D International Space Station
Explanation:
Get out your
red-blue glasses
and float next to the
International Space Station
(ISS), planet Earth's largest artificial moon.
This breathtaking stereo view was constructed from two separate
images
(S114-E-7245,
S114-E-7246)
recorded as the shuttle
orbiter Discovery undocked from the ISS
on August 6.
As seen here, from left to right
the ISS structure covers about 27 meters (90 feet).
The span from the automated
Progress supply ship docked in the
foreground to the
Destiny module hidden behind the
station structure is about 52 meters (171 feet) long, while the full
(top to bottom) reach of the solar arrays at the left would cover about
73 meters (240 feet).
Resupplied by Discovery, the ISS is currently operated by
the two member
Expedition 11 crew,
Sergei Krikalev and John Phillips.
APOD: 2005 August 16 - The International Space Station from Orbit
Explanation:
The International Space Station (ISS) is the largest
human-made object ever to orbit the
Earth.
Late last month and earlier this month, the station was
visited and resupplied by
space shuttle
Discovery.
The ISS is currently operated by the Expedition 11 crew, consisting a Russian and an American astronaut.
After departing the ISS, the crew of Discovery captured
this spectacular vista of the orbiting
space city.
Visible components include modules,
trusses, and expansive
solar arrays
that gather sunlight that is turned into needed
electricity.
APOD: 2005 July 29 - ISS and Discovery Transit the Sun
Explanation:
That large sunspot
near the right edge of the Sun is actually not a sunspot at all.
It's the
International Space Station
(ISS) and the Space
Shuttle Discovery on mission
STS-114.
In the past, many
skygazers
have spotted the space station and space shuttles as bright
stars gliding through
twilight skies, still
glinting in the
sunlight while orbiting 200 kilometers or so above the
Earth's surface.
But here, astronomer Anthony Ayiomamitis took advantage of
a rarer opportunity to
record
the spacefaring combination moving quickly
in silhouette across the solar disk.
He snapped the picture on Thursday, July 28th from
Athens, Greece.
Launched
on Tuesday, Discovery
joined with
the ISS Thursday,
making the already large space station seem to
loom
even larger.
APOD: 2005 July 27 - America Returns to Human Space Flight
Explanation:
NASA's launch of the massive
Space Shuttle Discovery yesterday
brought a nation known for its tremendous space program
back to human space flight.
Shuttle flights had been suspended for over
two years previously following the
tragic loss of the Space Shuttle Columbia
crew on 2003 February 1.
The complex, powerful
Space Shuttle Discovery lifted a crew of
seven into an Earth orbit that will bring them to the
International Space Station (ISS).
The shuttle crew will deliver supplies to the
ISS, perform repairs,
and test new methods for inspecting and repairing the shuttle's thermal protection system.
Three space walks are planned.
This Return to Flight Mission STS-114 is
pictured above launching from
Pad 39B on Cape Canaveral,
Florida.
APOD: 2005 May 28 - Himalayan Horizon From Space
Explanation:
This
stunning aerial view shows the rugged snow covered
peaks of
a Himalayan mountain range in Nepal.
The seventh-highest peak on the planet, Dhaulagiri,
is the high point
on the horizon at the left while
in the foreground lies the southern Tibetan Plateau of China.
But, contrary to appearances, this picture wasn't taken from
an airliner cruising at 30,000 feet.
Instead it was taken with a 35mm camera and telephoto lens by the
Expedition 1 crew aboard the
International Space Station --
orbiting 200 nautical
miles above the Earth.
The Himalayan mountains
were created by crustal plate tectonics
on planet Earth
some 70 million years ago, as the Indian plate began a
collision with the Eurasian plate.
Himalayan uplift still continues today at a rate of a
few millimeters per year.
APOD: 2004 September 15 - Above the Eye of Hurricane Ivan
Explanation:
Ninety percent of the houses on
Grenada were
damaged.
Such is the destructive force of
Hurricane Ivan, already one of the most powerful and
destructive hurricanes on
record.
And the storm will likely make landfall in southern USA tomorrow.
Ivan is the currently the third - and largest -
hurricane set to strike the US
this hurricane season.
The swirling eye of Hurricane Ivan was
photographed above
from the orbiting
International Space Station
(ISS) on Saturday as the storm's sustained
200 kilometer per hour winds wreaked havoc in the
Caribbean.
The bad news is that
hurricane season in the Atlantic typically lasts
until November 30, still over two months away.
The more immediate bad news is that tropical storm
Jeanne is next in line coming across the
mid-Atlantic Ocean and could pass
Puerto Rico sometime today.
APOD: 2004 May 30 - Astronaut at Work
Explanation:
Did you ever have a day where everything got turned
around and you just couldn't tell which way was up?
Fortunately, this didn't happen to astronaut
James S. Voss on 2000 May 21,
who spent six hours preparing to fix and upgrade the
International Space Station.
Voss is
shown above
anchored in the clutches of
Space Shuttle Atlantis'
mechanical arm, maneuvering outside the
shuttle's cargo bay high above
planet Earth.
This
space walk was the 85th in US history
and the fifth dedicated to the construction of the International Space Station.
The
STS-101 mission returned after successfully replacing the station's
batteries, lifting the station into a higher orbit,
and replenishing needed supplies.
APOD: 2003 October 6 - A Near Record Ozone Hole in 2003
Explanation:
As expected, the
ozone hole near Earth's
South Pole is back again this year.
This year's hole, being slightly larger than
North America, is larger than last year but short of
the record set on 2000 September 10.
Ozone is important because it shields us from damaging
ultraviolet
sunlight.
Ozone is vulnerable, though, to
CFCs and
halons being released into the atmosphere.
International efforts to reduce the use of these
damaging chemicals appear to be having a positive effect
on their atmospheric abundance.
The relatively large size of the
ozone hole this year, however, is attributed partly to
colder than normal air in the surrounding
stratosphere.
The above picture of the ozone hole was taken on September 11 by
TOMS on board the orbiting
Earth Probe satellite.
APOD: 2003 August 31 - The View from Everest
Explanation:
What would it be like to stand
atop
the tallest mountain on Earth?
To see a full panoramic vista from there, scroll right.
Visible are snow peaked mountains near and far,
tremendous cliffs, distant plateaus,
the tops of clouds, and a dark blue sky.
Mt. Everest stands 8.85 kilometers above sea level,
roughly the maximum height reached by international
airplane flights,
but much less than the 300 kilometers achieved by a
space shuttle.
Hundreds of people have tried and failed to climb the
behemoth by foot, a feat
first accomplished successfully in 1953.
About 1000 people have now
made it to the summit.
Roddy Mackenzie, who climbed the mountain in 1989, captured the
above image.
Mt. Everest lies in the
Himalayan mountains in the country of
Nepal.
In the
native language of Nepal,
the mountain's name is "Sagarmatha" which
means "forehead of the sky."
APOD: 2003 August 1 - Moons and Bright Mars
Explanation:
In this serene view,
the moons of Earth along with
the bright planet Mars shine above
the city of Turku near the southwestern tip of Finland.
Of course Earth's large natural satellite,
the
Moon, at a distance of 400,000 kilometers,
is by far the brightest object in this sky.
But growing brighter and
closer by the hour, Mars appears as
the impressively bright "star" at the right, about 64 million
kilometers from Turku.
Streaking across the twilight sky between the two celestial beacons,
Earth's largest artificial moon,
the International
Space Station,
orbits about 400 kilometers above the planet's surface.
To capture the moment, amateur astronomer
Petteri
Kankaro used a digital camera and combined exposures beginning
at 23:34 Universal Time on July 17th.
APOD: 2003 May 9 - International Space Station in Transit
Explanation:
A stunning telescopic image of the
International
Space Station
crossing in front of an eight day old Moon, this picture
was captured on April 11th.
But while Wednesday's leisurely
transit
of Mercury across the Sun
entertained observers all over the
dayside of planet Earth, the
audience for this lunar transit was more restricted.
Like other satellites
in low Earth orbit, the space
station moves quickly
through the sky.
Glinting in the sunlight near
sunset and sunrise,
its path strongly depends on the observer's longitude and latitude.
So, well-placed astronomer Tom Laskowski tracked the
orbiting space station
from a site near South Bend, Indiana, USA and
recorded a digital movie
of the fleeting, dramatic event.
This single frame from the movie has been enhanced to
bring out detail
in
the space station.
Seen below the lunar terminator at the lower left,
the International Space Station appears here at a distance
of just over 400 kilometers,
with the Moon nearly 400,000 kilometers away.
APOD: 2003 May 7 - The Southern Sky from the International Space Station
Explanation:
Look up from Earth's
South Pole,
and this stellar starscape is what you might see.
Alternatively,
this patch of sky
is also visible from many southern locations
as well as the orbiting
International Space Station,
where the
above image was recently recorded.
To the left of the photograph's center are the four stars that mark the
boundaries of the famous
Southern Cross.
The
band of stars, dust, and gas
crossing the middle of the photograph is part our
Milky Way Galaxy.
At the lower left is the dark
Coal Sack Nebula,
and the bright nebula on the far right is the
Carina Nebula.
The Southern Cross is such a famous constellation that it is
depicted on the
national flag of
Australia.
APOD: 2003 April 24 - Earth at Twilight
Explanation:
No sudden, sharp boundary marks the passage of day
into night in
this gorgeous view
of ocean and clouds over our
fair
planet Earth.
Instead, the shadow line or
terminator is
diffuse and shows
the gradual transition to darkness we experience as twilight.
With the Sun illuminating the scene from the right,
the cloud tops reflect gently reddened
sunlight filtered
through the dusty troposphere, the lowest layer of the planet's nurturing
atmosphere.
A clear high altitude layer,
visible along the dayside's upper edge,
scatters blue
sunlight and fades into the blackness of space.
This picture
actually is a single digital
photograph taken in June
of 2001 from the International Space Station
orbiting at an
altitude of 211
nautical miles.
APOD: 2003 January 5 - Atlantis to Orbit
Explanation:
Birds
don't fly this high.
Airplanes don't go this fast.
The Statue of Liberty
weighs less.
No species
other than human can even comprehend what is going on,
nor could any human just a millennium ago.
The launch of a
rocket bound for space is an event that
inspires awe
and challenges description.
Pictured above, the
Space Shuttle Atlantis lifted off to visit the
International Space Station
during the early morning hours of July 12.
From a standing start, the two million kilogram
rocket ship left to circle the
Earth where the
outside air is too thin to breathe and where there is
little
noticeable onboard gravity.
Rockets bound for space are now
launched from somewhere on Earth
about once a week.
APOD: 2003 January 2 - Mt. Etna Eruption Plume
Explanation:
Mt. Etna has been erupting for hundreds of thousands of years.
In late October of last year, however,
earthquakes triggered a particularly vigorous outburst from this
well known volcano on the
Italian island of Sicily.
Local schools were closed and
air-traffic re-routed as
hot lava poured out and
ash spewed out and settled as far away as
Libya.
Pictured above was the
Mt. Etna ash plume as it appeared to astronauts on the
International Space Station.
The view looks toward the southeast.
Light colored
smoke is due to
forest fires caused by
lava on the
volcano's north face.
APOD: 2002 December 28 - Mir Dreams
Explanation:
This
dream-like image
of Mir
was recorded by astronauts as the Space Shuttle
Atlantis
approached the Russian space station prior to docking during
the STS-76 mission.
Sporting spindly appendages and solar panels,
Mir resembles a whimsical flying insect hovering about 350 kilometers
above New Zealand's
South Island and the city of Nelson
near Cook Strait.
In late March 1996, Atlantis shuttled astronaut
Shannon W.
Lucid to Mir for a five month visit,
increasing Mir's occupancy from 2 to 3.
It returned to pick Lucid up and drop off
astronaut John Blaha during
the STS-79 mission
in August of that year.
Since becoming operational in 1986,
Mir has
been visited by over 100 spacefarers from
the nations of planet Earth including,
Russia, the United States, Great Britain,
Germany, France, Japan, Austria,
Kazakhstan and Slovakia.
After joint
Shuttle-Mir
training missions in support of the
International
Space Station, continuous occupation of Mir ended in August 1999.
The Mir was deorbited
in March 2001.
APOD: 2002 December 17 - Beefing Up the International Space Station
Explanation:
The International Space Station (ISS) will be the largest
human-made object ever to
orbit the
Earth.
The station is so large that it could not be
launched all at once --
it is being built piecemeal with large sections added
continually by flights of the
Space Shuttle.
To function, the ISS needs
trusses to keep it rigid and to route
electricity and liquid coolants.
These
trusses are huge, extending over 15 meters long,
and with masses over 10,000 kilograms.
Pictured above at the end of last month,
astronaut
Michael Lopez-Alegria works to install the
Port-One Truss.
On the right is the end of
Canadarm2, the robotic remote control arm of the
ISS.
APOD: 2002 December 8 - The International Space Station Expands Yet Again
Explanation:
The developing
International Space Station (ISS) has changed its
appearance yet again.
Earlier this month the
Space Shuttle
Endeavor visited the
ISS and installed the fourth of eleven pieces
that will compose the
Integrated Truss Structure.
The new P-1 Truss is visible on the left,
below the extended solar panels.
The world's foremost space outpost can be seen developing
over the past few years by comparing the
above image
to
past
images.
Also visible above are many
different types of modules, a robotic
arm, several wing-like
solar panels, and a supply ship.
Construction began on the
ISS in 1998 and the core
structure should be in place before 2005.
APOD: 2002 November 3 - The International Space Station Expands Again
Explanation:
The developing
International Space Station (ISS) has changed its
appearance yet again.
Last month the
Space Shuttle
Atlantis visited the
ISS and installed the third of eleven pieces
that will compose the
Integrated Truss Structure.
The new S-1 Truss is visible on the right,
below the extended solar panels across the top.
The world's foremost space outpost can be seen developing
over the past few years by comparing the
above image to
past
images.
Also visible above are many
different types of modules, a robotic
arm, several wing-like
solar panels, and a supply ship.
Construction began on the
ISS in 1998 and the core
structure should be in place before 2005.
Yesterday, the ISS celebrated its
second anniversary of continuous human habitation.
APOD: 2002 October 20 - The Space Shuttle Docked with Mir
Explanation:
Before there was the
International Space Station,
the reigning orbiting spaceport was Russia's Mir.
Pictured above in 1995, the United States
Space Shuttle Atlantis docked with the segmented
Mir.
During shuttle mission
STS-71, astronauts answered questions from
school students over
amateur radio and performed
science experiments
aboard Spacelab.
The Spacelab experiments helped to increase understanding of the
effects of long-duration space flights on the
human body.
Last year, after 15 years of successful service, the decaying
Mir space station broke up as it
entered the
Earth's atmosphere.
APOD: 2002 July 23 - The View from Everest
Explanation:
What would it be like to stand
atop
the tallest mountain on Earth?
To see a full panoramic vista from there, scroll right.
Visible are snow peaked mountains near and far,
tremendous cliffs, distant plateaus,
the tops of clouds, and a dark blue sky.
Mt. Everest stands 8.85 kilometers above sea level,
roughly the maximum height reached by international
airplane flights,
but much less than the 300 kilometers achieved by a
space shuttle.
Hundreds of people have tried and failed to climb the
behemoth by foot, a feat
first accomplished successfully in 1953.
About 1000 people have now made it to the summit.
Roddy Mackenzie, who climbed the mountain in 1989, captured the
above image.
Mt. Everest lies in the
Himalayan mountains in the country of
Nepal.
In the
native language of Nepal,
the mountain's name is "Sagarmatha" which
means "goddess of the sky."
APOD: 2002 April 26 - Comet Ikeya-Zhang Meets The ISS
Explanation:
Still catching the Sun's rays, the
International
Space Station (ISS) cruises across the early evening
sky
above Tomahawk, Wisconsin, USA.
Recorded on April 9 around 9 pm CDT in a 30 second exposure, the
sunlit space station traced this bright streak moving east
(right) through the
constellation
Cassiopeia.
Below lies
Comet Ikeya-Zhang
sporting a visible tail.
But while this photogenic
comet is now fading from view,
the ISS will be
getting brighter.
Hours after this picture was taken, the Space Shuttle Atlantis
docked with
the ISS, bringing another
structure to add to the growing
orbital outpost.
APOD: 2002 April 23 - The Newly Expanded International Space Station
Explanation:
What does the developing
International Space Station (ISS) look like now?
After delivering and deploying a crucial first
backbone-like component last week, the
Space Shuttle
Atlantis took an inspection lap around the
space station.
The newly installed truss is visible toward the center of the
above image.
Also visible are many
different types of modules, a robotic
arm, several wing-like
solar panels, and a supply ship.
Construction began on the
ISS in 1998 and the core
structure should be in place before 2005.
APOD: 2002 April 15 - A New Truss for the International Space Station
Explanation:
The
International Space Station (ISS) is being fitted with a
backbone.
During the
present visit of
Space Shuttle
Atlantis, astronauts are installing a
huge truss on the growing space outpost.
The truss is over 13 meters long and about 4.5 meters wide.
Dubbed
Starboard 0, or S0 (pronounced S-Zero) for short,
the truss will route
electricity, vent excess heat, and allow for
future ISS expansion.
Pictured above, the truss was lifted out of the shuttle's cargo bay by the
station's robotic Canadarm2.
APOD: 2002 January 2 - International Space Station Over Earth
Explanation:
High above a cloudy Earth, the
International Space Station (ISS) orbits silently.
The Space Shuttle
Endeavor Crew took the above picture as they departed
the space station in mid-December.
Endeavor brought up
three new astronauts to occupy the ISS and carried home the members of
Expedition Three,
a trio that has been housed in the
ISS since August.
Highlights of this
Endeavor mission included fixing a solar panel and maneuvering the station to avoid a large piece of
passing space junk.
Visible in the
above picture are the space station's
robot manipulator arm
as well as several modules and
solar arrays.
APOD: 2001 December 26 - Himalayan Horizon From Space
Explanation:
This
stunning aerial view shows the rugged snow covered
peaks of
a Himalayan mountain range in Nepal.
The seventh-highest peak on the planet, Dhaulagiri,
is the high point
on the horizon at the left while
in the foreground lies the southern Tibetan Plateau of China.
But, contrary to appearances, this picture wasn't taken from
an airliner cruising at 30,000 feet.
Instead it was taken with a 35mm camera and telephoto lens by the
Expedition 1 crew aboard the
International Space Station --
orbiting 200 nautical
miles above the Earth.
The Himalayan mountains
were created by crustal plate tectonics
on planet Earth
some 70 million years ago, as the Indian plate began a
collision with the Eurasian plate.
Himalayan uplift still continues today at a rate of a
few millimeters per year.
APOD: 2001 December 17 - Leaving the International Space Station
Explanation:
It was time to go home.
During their eight days aboard the
Earth-orbiting
International Space Station (ISS),
ESA Flight Engineer
Claudie Haigner, Russian Commander
Victor Afanasyev, and Russian Flight Engineer Konstantin Kozeev
had completed several experiments and
successfully delivered a new lifeboat.
The lifeboat was actually the new
Soyuz capsule they arrived in -- they
returned home in an older Soyuz capsule that
had been left six months ago.
Haigner, an expert in
rheumatology and
neuroscience, studied the development of
frog
embryos under
microgravity conditions.
Pictured above on
October 31, their Soyuz spacecraft
undocks from the ISS while
dark space and a blue Earth hover in the
background.
APOD: 2001 October 12 - Space Station and Space Shuttle: Backyard View
Explanation:
Knowing when and where
to look, many enthusiastic sky gazers have
been able to spot the International Space Station (ISS) as
a bright star streaking
through the twilight.
But with a digital camera and a small telescope, recognizable
images
are possible too.
Astronomer Ricardo Borba
offers this example of the
Space Shuttle
Discovery docked with
the ISS, recorded this August from
his backyard in Ottawa, Canada.
Operating a digital video camera on an 8 inch reflecting telescope,
Borba tracked the Earth-orbiting pair by hand.
Unwanted telescope motion and atmospheric
blurring caused most of the
video frames to be indistinct, still the single
best frame (left) from his video sequence is amazingly sharp.
For comparison, he constructed a computer generated
image (right) showing the approximate orientation of the Shuttle/ISS docking
configuration based on
virtual
3D models available
on the web.
APOD: 2001 July 23 - Atlantis to Orbit
Explanation:
Birds
don't fly this high.
Airplanes don't go this fast.
The Statue of Liberty
weighs less.
No species
other than human can even comprehend what is going on,
nor could any human just a millennium ago.
The launch of a
rocket bound for space is an event that
inspires awe
and challenges description.
Pictured above, the
Space Shuttle Atlantis lifted off to visit the
International Space Station
during the early morning hours of July 12.
From a standing start, the two million kilogram
rocket ship left to circle the
Earth where the
outside air is too thin to breathe and where there is
little
noticeable onboard gravity.
Rockets bound for space are now
launched from somewhere on Earth
about once a week.
APOD: 2001 July 13 - Welcome to the Moon Hotel
Explanation:
The most detailed proposal
so far for a hotel and resort destination
on the Moon (!) has been prepared by
Dutch
architect Hans-Jurgen Rombaut.
The harsh
lunar environment
posed serious
design challenges but the Moon's low,
one-sixth-Earth gravity,
and the absence of wind were an
architectural boon allowing a much more slender and fragile-looking
building than would have been
possible on Earth.
Illustrated here, the structure's two 160 meter high needle-like
towers soar over
the rim of a deep canyon as planet Earth hangs in the
lunar sky.
To shield the interior, Rombaut designed 50 centimeter thick walls
with two outer layers of Moon rock and a 35
centimeter layer of
water
held between glass planes.
The water absorbs energetic cosmic rays and along with the
rock helps keep the temperature constant.
Windows are framed as holes in the rock layers.
Construction
materials are intended to be manufactured
on the Moon itself.
This Moon Hotel design is welcomed by the international Lunar
Explorers Society, LUNEX,
who hope to construct a robotic
Moon base by 2015,
ultimately
supporting a lunar village by 2040.
APOD: 2001 April 30 - Approaching the International Space Station
Explanation:
Earlier this month the crew of the
US Space Shuttle Endeavor took in
this view as they approached the developing
International Space Station (ISS).
The
Endeavor and
ISS crew installed
Italy's
Raffaello, a Multi-Purpose Logistics Module
and successfully deployed
Canada's Canadarm2, a robot remote-controlled arm that
can move about the outside of
the station.
The shuttle undocked from the
ISS yesterday and is scheduled to return to Earth today.
A manned
Russian
Soyuz spacecraft is scheduled to dock with
Earth's busiest orbiting outpost early today.
APOD: 2001 April 23 - Space Shuttle Lifts Off for Space Station
Explanation:
Last Thursday,
Space Shuttle Endeavor lifted off on course
for the latest round of building the
International Space Station (ISS) in orbit around Earth.
One of the highlights of the
11-day mission promises to be the installation of
Canadarm2, a robotic arm that will
assist in the future construction and utilization of the
ISS.
Canadarm2, a larger and more sophisticated version of the
shuttle's own robotic arm,
will be able to move around
the station's exterior.
This is the ninth
shuttle mission to build the ISS --
many more are planned over the next several years.
When completed, the ISS should enclose about the
same room as the passenger cabin of a
747 jet.
APOD: 2001 March 20 - Discovery Spring
Explanation:
Welcome to the
equinox!
Moving northward in Earth's sky, today
the Sun crosses the celestial
equator at 13:31
Universal
Time bringing Spring to the north and Fall to the south.
The change of season is known as an equinox as
the Sun rises due
east on the horizon and sets due west -- providing an
equal night, 12 night and 12 daylight hours,
for both northern and southern hemispheres.
In this picture from March 8, the Sun peers
over the eastern horizon at the space shuttle Discovery's
dramatic morning launch on mission STS-102.
Having delivered supplies and taxied crew to the
International Space Station,
Discovery will remain in orbit for this
first day of northern hemisphere Spring.
Discovery is scheduled
to
land at
Kennedy Space Center
in Florida early tomorrow.
APOD: 2001 February 28 - A Space Station Meets its Destiny
Explanation:
The International Space Station (ISS) had a date
with Destiny earlier this month.
More specifically, the crew of the
Space Shuttle Atlantis
installed the science laboratory named
Destiny on the
ISS.
Destiny,
pictured here, will also serve as a control center for the Earth
orbiting space station.
To help install this module, space shuttle astronauts conducted the
100th space walk by an American,
an event that occurred nearly 40 years after
Ed White first ventured outside of his Gemini 4 spacecraft.
The space shuttle's crew took the
above picture after their
spacecraft had undocked from the space station.
Over two hundred kilometers below lies the
Rio Negro region of
Argentina.
APOD: 2000 December 14 - International Space Station Trail
Explanation:
Still under construction, the
International
Space Station is becoming one
of
the brightest, fastest moving "stars" in the heavens.
Despite illuminated clouds and bright light from a
nearly full moon (lower left),
this 5 minute time exposure easily captures
the Space Station's trail as it arcs through early evening skies
above Palm Beach Gardens, Florida, USA
on December 9.
At the time,
the
Space Shuttle Endeavour had undocked
and moved away from the orbiting platform,
the shuttle crew having just completed
the installation
of large solar panels to power the Space Station's systems.
Sunlight glinting off the large, shiny panels is likely the source
of the brief flare visible along the track.
Astrophotographer Doug Murray and colleague report that both
Shuttle and Space Station
were
visible separately and on
close inspection
of this image they do produce distinct, parallel arcs.
At the extreme right hand edge of the picture,
the
trails pass
very near the brightest "star" in the night sky,
Venus.
APOD: 2000 November 3 - New Moons For Saturn
Explanation:
Which planet has the most moons?
For now, it's Saturn.
Four newly discovered
satellites bring the ringed planet's
total to twenty-two, just edging out
Uranus' twenty-one for
the most
known moons in the solar system.
Of course, the newfound
Saturnian
satellites are not
large and
photogenic.
The faint S/2000 S 1, the first discovered in the year 2000,
is the tiny dot indicated at the lower right of this
August 7th image made with the ESO 2.2 meter telescope at
La Silla, Chile.
(An eye-catching spiral galaxy at the upper left is in
the very distant background!)
Unlike Saturn's larger moons whose almost circular
orbits lie near the planet's equatorial plane,
all four newly discovered moons have
irregular,
skewed orbits drifting far from the planet.
With sizes in the 10 to 50 kilometer range, they are
are likely captured asteroids.
The international team of astronomers involved in the discoveries
hopes to get many observations of
the tiny satellites
allowing accurate orbital computations before
Saturn is
lost in the solar glare around March 2001.
The team has also found several other irregular satellite
candidates which are now being followed.
Saturn's only previously known irregular satellite is
Phoebe,
discovered over 100 years ago by W. H. Pickering,
APOD: 2000 September 18 - Approaching the International Space Station
Explanation:
Last Monday the crew of Space Shuttle Atlantis took in
this view as they approached the developing
International Space Station (ISS).
From top to bottom, the astronauts saw a station
currently consisting of the Progress supply module, the
Zvezda service module, the
Zarya cargo module, and the
Unity connecting module.
Never before had astronauts seen the
station since the remote-controlled additions of Progress and
Zvezda.
Energy collecting flat solar panels can be seen extending from some of the modules.
Soon after this picture was taken, Atlantis docked with the
ISS at the
Unity end.
The astronauts have
worked hard unloading supplies,
installing and testing equipment,
and even planning to reboost the
floating space station
to a higher orbit.
The Shuttle and its entire crew are
scheduled to return to Earth Wednesday.
The
Space Shuttle Discovery is then
scheduled to visit the ISS in two weeks.
APOD: 2000 August 26 - Mir Dreams
Explanation:
This dream-like image
of Mir was recorded
by astronauts as
the Space Shuttle
Atlantis
approached the Russian space station
prior to docking during
the STS-76 mission.
Sporting spindly appendages and solar panels,
Mir resembles a whimsical flying insect hovering about 350 kilometers
above New Zealand's
South Island and the city
of Nelson,
near Cook Strait.
In late March 1996, Atlantis shuttled astronaut
Shannon W.
Lucid to Mir for a five month visit,
increasing Mir's occupancy from 2 to 3.
It returned to pick Lucid up and drop off
astronaut John Blaha during
the STS-79 mission
in August of that year.
Since becoming operational in 1986,
Mir has
been visited by over 100 spacefarers from
the nations of planet Earth including,
Russia, the United States, Great Britain,
Germany, France, Japan, Austria,
Kazakhstan and Slovakia.
After joint
Shuttle-Mir
training missions in support of the
International
Space Station, continuous occupation of Mir ended in August 1999.
Mir is still in orbit and its operation is now being pursued by
commercial
interests.
APOD: 2000 May 31 - Astronaut at Work
Explanation:
Did you ever have a day where everything got turned
around and you just couldn't tell which way was up?
Fortunately, this didn't happen to astronaut
James S. Voss on May 21,
who spent six hours preparing to fix and upgrade the
International Space Station.
Voss is
shown above
anchored in the clutches of
Space Shuttle Atlantis'
mechanical arm, maneuvering outside the
shuttle's cargo bay high above
planet Earth.
This
space walk was the 85th in US history
and the fifth dedicated to the construction of the International Space Station.
The
STS-101 mission returned early Monday morning
after successfully replacing the station's
batteries, lifting the station into a higher orbit,
and replenishing needed supplies.
In
several years, when the
International Space Station is complete,
a crew of up to seven astronauts will live and
work in a volume similar to a
747 jumbo jet.
APOD: December 8, 1999 - Moon Struck
Explanation:
Craters produced by ancient impacts on the
airless Moon have long been a
familiar sight.
But now observers have seen elusive
optical flashes on the lunar surface -
likely the fleeting result of impacting meteoroids.
Orchestrated by David Dunham, president of the
International Occultation Timing Association (IOTA),
video recordings made with modest equipment and
visual telescopic observations have, for the first time,
detected and confirmed a total of six flashes on the Moon's dark side.
The flashes,
some initially as bright as a third magnitude star,
were all seen within hours of the peak of this year's
Leonid meteor shower.
Their locations are indicated by the red Xs on this
projection of the Moon as it appeared on the night of November 18.
Similar flashes would have been difficult to see if
viewed against the Moon's brightly lit portion.
It has been estimated that the brightest flashes were made by
meteoroids weighing around a tenth of a kilogram, resulting
in lunar craters about one meter across.
And ... the
next chance to observe lunar impact flashes
is coming up!
Enterprising astronomers interested in long distance
lunar prospecting
should be monitoring the dark side of
a nearly first quarter Moon during the
Geminids meteor shower which will peak
around December 13.
APOD: October 13, 1999 - Ozone Hole Reduced
Explanation:
Although a
new ozone hole has formed again this year over the
South Pole,
this time it is a little bit smaller than the
year before.
Ozone is important because it shields us from damaging
ultraviolet sunlight.
Ozone is vulnerable, though, to
CFCs and
halons being released into the atmosphere.
International efforts to reduce the use of these
damaging chemicals really are having a positive effect
on their atmospheric abundance.
This year, however, the slightly reduced size of the
ozone hole is mostly due to relatively mild weather,
which reduces the efficiency of
ozone depletion.
In the above false-color picture taken earlier this month,
low ozone levels are shown in blue.
APOD: February 27, 1999 - Hamlet of Oberon
Explanation:
What's in a name?
Since 1919, the
International Astronomical Union has been
charged with the task of establishing
"conventional" nomenclature for planets, satellites,
and surface features.
For the remote
Uranian system of moons, namesakes from
Shakespearean works have been chosen.
Thus Oberon, king of the mid-summer night fairies, is also
Uranus' most distant and second largest moon.
Hamlet is the tragically dark, large and princely
crater on its surface (right of center).
The above image represents known surface
features of Oberon and
was constructed by the U.S. Geological Survey (USGS) based on data from
NASA's robot explorer Voyager 2.
In 1986, Voyager 2
flew through the Uranian system -
so far it has been
the only spacecraft to do so.
APOD: February 23, 1999 - Construction of International Space Station Begins
Explanation:
Move over
Mir, here comes the
International Space Station.
In December 1998, the crew of
Space Shuttle Endeavour
started construction
by joining the U.S.-built Unity node with the Russian-built
Zarya module. A close look at the
above IMAX(r) photograph will reveal
two astronauts working on Unity.
Below on Earth, the terminator between night and day is visible.
The International Space Station's low 250-mile Earth
orbit causes it to experience one complete
day/night cycle in about 90 minutes.
APOD: December 10, 1998 - Assembling The International Space Station
Explanation:
Batteries and solar panels were included with this version of
the International Space Station (ISS) but some
assembly is still required.
On Saturday, December 5th, the
STS-88 crew of the Space Shuttle Endeavor achieved the
in orbit docking of the
Zarya and
Unity (foreground) ISS modules.
On Monday, astronauts
James Newman (left) and
Jerry Ross continued the assembly
procedures connecting power and data cables
during the first of three planned spacewalks.
Ground controllers were then able to successfully activate the ISS.
Now orbiting planet Earth at an altitude of about 248 miles,
Endeavour and
the ISS are reported to be in excellent shape and
crew members plan to enter the new space station today.
Five Americans, one Russian, and the Unity module itself
were lifted into orbit by the shuttle on Friday, December 4,
while the Zarya (sunrise) module was launched on a
Proton rocket from the
Baikonur Cosmodrome in Kazakstan on November 20.
APOD: October 15, 1998 - A Great Day For SOHO
Explanation:
The last 10 days have been
great days for SOHO,
the space-based SOlar and Heliospheric Observatory.
Contact was completely lost with this international research
spacecraft over 3 months ago but
recovery teams have reacquired control of SOHO and,
beginning October 5th, have been successfully
switching on its scientific instruments.
This October 13th view of the Sun in the light of
ionized Helium atoms
was recorded by the restored EIT instrument.
It shows bright
active regions and
lofty prominences
above the solar limb.
North is toward the left rather than the top as the spacecraft's
orientation has not yet been fully adjusted.
(For a full Sun / full resolution view, click on the picture!)
With the solar cycle approaching a maximum in the coming years,
excitement continues to build as it becomes very likely that SOHO
will be able to resume its unprecedented exploration of
solar phenomena.
APOD: September 11, 1998 - Help Map The Moon
Explanation:
You can help map
the Moon.
Early tomorrow morning
(Saturday, September 12) the Moon will occult, or pass in front of,
the bright star
Aldebaran as viewed from some Southern and Eastern areas
of the U.S. as well as regions in the Caribbean Sea,
Nova Scotia, Newfoundland, Mexico, and Central America.
Aldebaran will
disappear behind the bright edge of the third quarter
moon and
reappear behind the darkened edge.
Accurately timed home video camera recordings
from different locations
can be used to make improved maps of the height of the lunar terrain
at these occultation points.
Interested?
Follow
the instructions on the
International Occultation Timing Association HomePage
which detail how to tape a familiar TV channel,
take your running camcorder outside to record the occultation,
and then return to tape a few more minutes of the TV channel.
(First, determine if the occultation will be visible from your location!)
You can then donate your tape by mailing it to the address given.
Leave yourself plenty of time
for a practice run and be sure to check the weather
before going to a lot of trouble!
This mosaic
mapping the North polar region of the lunar surface was
constructed from images recorded by the Galileo spacecraft in 1992.
APOD: June 5, 1998 - Neutrinos in the Sun
Explanation:
Neutrinos,
along with
things like electrons and quarks, are fundamental pieces of
matter according to
physicists' Standard Model.
But neutrinos are hard to detect.
Readily produced
in nuclear reactions and
particle collisions, they can easily pass completely through planet
Earth without once interacting with any other particle.
Constructed in an unused mine in Japan,
an ambitious large-scale experiment
designed to detect and study neutrinos is known
as Super-Kamiokande or "Super-K".
Only(!) 500 days worth of data was needed to produce
this "neutrino image" of the Sun,
using Super-K
to detect the neutrinos from nuclear fusion
in the solar interior.
Centered on the Sun's postion, the picture covers a significant
fraction of the sky (90x90 degrees in R.A. and Dec.).
Brighter colors represent a larger flux of neutrinos.
News:
In a tantalizing
recent announcement, an
international collaboration of
Super-K researchers has
now presented evidence that the ghostly neutrinos
undergo quantum mechanical oscillations,
changing their particle identities and quantum properties over time.
Theorists have considered neutrinos to be massless particles
but these oscillations would imply that they
have a very small (but nonzero) mass.
Astrophysicists are
taking note because even
a small mass for ubiquitous, nearly undetectable neutrinos would
make them accountable for a substantial fraction of the
total mass of our Universe, influencing and perhaps determining
its ultimate fate!
A measurable mass for neutrinos would also make them candidates
for the
mysterious dark matter known
to affect the motions of stars and galaxies,
while proof of neutrino oscillations would be a step toward
resolving the decades old
Solar Neutrino Problem.
Even skeptical scientists will be waiting impatiently
to see if these results are independently confirmed.
APOD: January 31, 1998 - Hamlet of Oberon
Explanation:
What's in a name?
Since 1919, the
International Astronomical Union has been
charged with the task of establishing
"conventional" nomenclature for planets, satellites,
and surface features.
For the remote
Uranian system of moons, namesakes from
Shakespearean works have been chosen.
Thus Oberon, king of the mid-summer night fairies, is also
Uranus' most distant and second largest moon.
Hamlet is the tragically dark, large and princely
crater on its surface (right of center).
The above image represents known surface
features of Oberon and
was constructed by the U.S. Geological Survey (USGS) based on data from
NASA's robot explorer Voyager 2.
In 1986, Voyager 2
flew through the Uranian system -
so far it has been
the only spacecraft to do so.
APOD: December 10, 1997 - Sprint the Flying Space Camera
Explanation:
Yes, but can your soccer ball do this?
The ball near the middle of the above photograph is actually a robotic camera
designed to float about a
Space Shuttle and the
International Space Station
and take pictures. Named "Sprint", it is NASA's first Autonomous Extravehicular
Activity Robotic Camera (AERCam) and was tested earlier
this month by the
crew
of Space Shuttle Columbia. Sprint's diameter is actually about
50 percent larger than a soccer ball, and
astronauts make a goal of not kicking it.
APOD: May 8, 1997 - Detailing Hale-Bopp
Explanation:
This enhanced composite image
detailing structure in the coma and dust tail of Hale-Bopp was recorded May 5 -
one day before the comet's passage from
north to south across
the plane of Earth's orbit.
As the comet descends into murky
twilight for northern hemisphere
observers it will become increasingly easy to view from the south.
Along with Southern Hemisphere observers,
astronomers and a fleet of spacecraft of
the International Solar-Terrestrial Physics program
have been anxiously
awaiting this north/south crossing.
The comet's interaction with the changing equatorial
solar wind and magnetic field
during this crossing is expected to
produce distortions and disconnections of Hale-Bopp's ion tail.
Whisker-like structures, probably part of the ion tail, are
visible above extending from the lower left of the bright coma.
APOD: December 24, 1996 - A Mirry Christmas
Explanation:
Thinking about spending the Holiday Season in
low Earth orbit?
Astronaut John Blaha and his cosmonaut colleagues
Valeri Korzun and Alexander Kaleri are
doing just that onboard the Russian Mir spacestation.
You can
e-mail them Seasons Greetings.
Blaha replaced Shanon Lucid
as a Mir resident during
the STS-79 mission flown
by the Space Shuttle Atlantis
and is scheduled to be
replaced by Jerry Linenger when Atlantis makes another shuttle run to Mir
during the
STS-81 mission.
The Mir is seen here 200 miles above the Earth
as the sun sets following the latest Atlantis undocking.
NASA shuttle flights to the Mir
are part of the
Phase 1 program for construction of
the International Space Station.
APOD: September 28, 1996 - A Soyuz at Mir
Explanation:
Pictured above is a three person
Russian Soyuz capsule
with wing-like solar panels extended, joined to the
Mir space station.
In Russian soyuz means "union" and indeed one of the milestones achieved by
a Soyuz spacecraft was an orbital union with a
US Apollo command module during the
first international space mission
(Apollo-Soyuz) in 1975.
The Soyuz TM spacecraft are specially modified
for use with the Mir as ferries for
cosmonauts and
astronauts
and also as lifeboats, should the need
arise. This image is from an electronic still camera used by
the crew of the
Space Shuttle Atlantis during their latest
Mir visit to pick up astronaut Shannon Lucid
and drop off John Blaha.
APOD: March 10, 1996 - Mir is 10
Explanation:
The first module of the
Russian Space Agency's Mir Space Station
was launched into orbit 10 years ago (on February 20, 1986).
Mir has since been substantially expanded in orbit by
adding additional modules including
the Kvant Astrophysics Module (1987)
and recently a docking module.
NASA's Space Shuttle Atlantis
was modified to allow it to dock with Mir in 1995
(STS-71,,
STS 74) beginning a
series of Shuttle-Mir flights scheduled to continue through 1997.
In this wide angle view - poised above planet
Earth with sunlight glinting from solar panels - Mir
and Atlantis are seen connected via the docking module from
the perspective of the shuttle payload bay. The image is
from an IMAX movie frame
taken during the STS 74 mission.
In late 1997, building on this jointly developed understanding and
experience, the US and Russia will launch the
first modules of the
International Space Station.
APOD: September 29, 1995 - The International Ultraviolet Explorer
Explanation:
The International Ultraviolet Explorer (IUE)
was launched by a
NASA Delta rocket
in 1978 to provide a space telescope for
ultraviolet astronomy. A collaborative project among NASA,
ESA and the
British SRC (now PPARC) agencies, IUE's estimated lifetime was 3 to 5 years.
Amazingly, 17 years and 8 months later, it continues to operate, having
made over 100,000
observations
of comets, planets, stars, novae, supernovae, galaxies, and quasars.
The IUE
story is a truly remarkable but little
known success story which will continue.
To reduce costs, on September 30, 1995, the IUE team
at GSFC will turn over its science operations to the
ESA ground station in
Villafranca, Spain where the ESA/PPARC teams will
continue to make astronomical observations.
Congratulations to the
GSFC team
for outstanding service to astronomy. Good luck to IUE and best wishes
for continued success!