APOD: June 16, 1995 - Neutron Star Earth
If the Earth could somehow be transformed to the ultra-high density of a
neutron star, it might appear as it does in the above computer generated
figure. Due to the very strong gravitational field, the neutron star
distorts light from the background sky greatly. If you look closely, two
images of the constellation Orion are visible. The gravity of this
particular neutron star is so great that no part of the neutron star is
blocked from view - light is pulled around by gravity even from the back of
the neutron star.
APOD: June 20, 1995 - Pleiades Star Cluster
The Pleiades star cluster, M45, is one of the brightest star clusters
visible in the northern hemisphere. It consists of many bright, hot stars
that were all formed at the same time within a large cloud of interstellar
dust and gas. The blue haze that accompanies them is due to very fine dust
which still remains and preferentially reflects the blue light from the
stars.
APOD: June 21, 1995 - Supernova 1987a Aftermath
In 1987 a star in one of the Milky Way's satellite galaxies exploded. In
1994 the Hubble Space Telescope, in orbit around the earth, took a very
detailed picture of the remnants of this explosion. This picture, above,
showed unusual and unexpected rings, and astronomers are not sure how they
formed.
APOD: June 22, 1995 - Earth from Apollo 17
In 1972 Astronauts on the United States's last lunar mission, Apollo
17, took this picture looking back at the Earth on their way to the moon.
The continents of Antarctica and Africa are visible below the
delicate wisps of white clouds.
APOD: June 23, 1995 - Gamma Ray Sky Map
What if you could "see" gamma rays? This computer processed image
represents a map of the entire sky at photon energies above 100 million
electron Volts. These gamma-ray photons are more than 10,000 times more
energetic than visible light photons and are blocked from the Earth's
surface by the atmosphere. In the early 1990s NASA's Compton Gamma Ray
Observatory, in orbit around the Earth, scanned the entire sky to produce
this picture. A diffuse gamma-ray glow from the plane of our Milky Way
Galaxy is clearly seen across the middle. The nature and even distance to
some of the fainter sources remain unknown.
APOD: June 25, 1995 - Jupiter from Voyager
Imagine a hurricane that lasted for 300 years! This picture of the planet
Jupiter was taken by the Voyager 1 spacecraft as it passed the planet in
1979. Jupiter, a gas giant planet with no solid surface, is the largest
planet in the solar system and is made mostly of the hydrogen and helium.
Clearly visible in the photo is the Great Red Spot, a giant, hurricane-like
storm system that rotates with the clouds of Jupiter. It is so large three
complete Earths could fit inside it. Astronomers have observed this giant
storm on Jupiter for over 300 years.
APOD: June 26, 1995 - Spiral Galaxy M100
The M100 galaxy is a large spiral galaxy similar to our own Milky Way,
containing over 100 billion stars. It is over 150 million light years
away, so the light we see left when dinosaurs roamed the Earth. The picture
was taken in 1993 with the Wide Field and Planetary Camera 2 on board the
Hubble Space Telescope.
APOD: June 27, 1995 - An Ultraviolet Image of M101
This giant spiral galaxy, Messier 101 (M101), was photographed by the
Ultraviolet Imaging Telescope onboard the Space Shuttle Endeavour during
the Astro-2 mission (March 2 - 18, 1995). The image has been computer
processed so that the colors represent the intensity of ultraviolet light.
Pictures of galaxies like this one show mainly clouds of gas containing
newly formed stars many times more massive than the sun, which glow
strongly in ultraviolet light. In contrast, visible light pictures of
galaxies tend to be dominated by the yellow and red light of older stars.
Ultraviolet light, invisible to the human eye, is blocked by ozone in the
atmosphere so ultraviolet pictures of celestial objects must be taken from
space.
APOD: June 28, 1995 - The Cat's Eye Nebula
Three thousand light years away, a dying star throws off shells of glowing
gas. This Hubble Space Telescope image reveals "The Cat's Eye Nebula" to
be one of the most complex "planetary nebulae" known. In fact, the
features seen in this image are so complex that astronomers suspect the
visible central star may actually be a double star system. The term
planetary nebula, used to describe this general class of objects, is
misleading. Although these objects may appear round and planet-like in
small telescopes, high resolution images reveal them to be stars surrounded
by cocoons of gas blown off in the late stages of evolution.
APOD: June 29, 1995 - The Earth-Moon System
A double planet? From 4 million miles away on December 16, 1992, NASA's
robot spacecraft Galileo took this picture of the Earth-moon system. The
bright, sunlit half of the Earth contrasts strongly with the darker subdued
colors of the moon. Our moon is one of the largest moons in the solar
system. It is even larger than the planet Pluto. In this picture, the
Earth-moon system actually appears to be a double planet.
APOD: June 30, 1995 - Ida and Dactyl: Asteroid and
Moon
An asteroid with a moon! The robot spacecraft Galileo whose primary
mission is to explore the Jupiter system, has encountered and photographed
two asteroids during its long journey to Jupiter. The second asteroid it
photographed, called Ida, was discovered to have a moon which appears as a
small dot to the right of Ida in this picture. The tiny moon, named Dactyl,
is about one mile across, while the potato shaped Ida measures about 36
miles long and 14 miles wide. Dactyl is the first moon of an asteroid ever
discovered. The names Ida and Dactyl are based on characters in Greek
mythology.