Astronomy Picture of the Day Search Results for "Rosette"

APOD: 2024 February 14 – Rosette Deep Field
Explanation: Can you find the Rosette Nebula? The large, red, and flowery-looking nebula on the upper left may seem the obvious choice, but that is actually just diffuse hydrogen emission surrounding the Cone and Fox Fur Nebulas. The famous Rosette Nebula is really located on the lower right and connected to the other nebulas by irregular filaments. Because the featured image of Rosetta's field is so wide and deep, it seems to contain other flowers. Designated NGC 2237, the center of the Rosette nebula is populated by the bright blue stars of open cluster NGC 2244, whose winds and energetic light are evacuating the nebula's center. The Rosette Nebula is about 5,000 light years distant and, just by itself, spans about three times the diameter of a full moon. This flowery field can be found toward the constellation of the Unicorn (Monoceros).

APOD: 2024 February 9 - When Roses Aren't Red
Explanation: Not all roses are red of course, but they can still be very pretty. Likewise, the beautiful Rosette Nebula and other star forming regions are often shown in astronomical images with a predominately red hue, in part because the dominant emission in the nebula is from hydrogen atoms. Hydrogen's strongest optical emission line, known as H-alpha, is in the red region of the spectrum. But the beauty of an emission nebula need not be appreciated in red light alone. Other atoms in the nebula are also excited by energetic starlight and produce narrow emission lines as well. In this close-up view of the Rosette Nebula, narrowband images are mapped into broadband colors to show emission from Sulfur atoms in red, Hydrogen in green, and Oxygen in blue. In fact, the scheme of mapping these narrow atomic emission lines (SHO) into the broader colors (RGB) is adopted in many Hubble images of emission nebulae. This image spans about 50 light-years across the center of the Rosette Nebula. The nebula lies some 3,000 light-years away in the constellation Monoceros.

APOD: 2024 January 31 – Camera Orion Rising
Explanation: What does Orion rising look like to a camera? During this time of the year, the famous constellation is visible to the southeast just after sunset. From most Earthly locations, Orion's familiar star pattern, highlighted by the three-stars-in-a-row belt stars, rises sideways. An entire section of the night sky that includes Orion was photographed rising above Śnieżka, a mountain on the border between Poland and the Czech Republic. The long duration exposure sequence brings up many faint features including the Orion and Flame Nebulas, both encompassed by the curving Barnard's Loop. The featured wide-angle camera composite also captured night sky icons including the blue Pleiades star cluster at the image top and the red Rosette Nebula to the left of Orion. Famous stars in the frame include Procyon, Betelgeuse, Rigel and Aldebaran. Orion will appear successively higher in the sky at sunset during the coming months.

APOD: 2024 January 23 – Deep Nebulas: From Seagull to California
Explanation: How well do you know the night sky? OK, but how well can you identify famous sky objects in a very deep image? Either way, here is a test: see if you can find some well-known night-sky icons in a deep image filled with faint nebulosity. This image contains the Pleiades star cluster, Barnard's Loop, Horsehead Nebula, Orion Nebula, Rosette Nebula, Cone Nebula, Rigel, Jellyfish Nebula, Monkey Head Nebula, Flaming Star Nebula, Tadpole Nebula, Aldebaran, Simeis 147, Seagull Nebula and the California Nebula. To find their real locations, here is an annotated image version. The reason this task might be difficult is similar to the reason it is initially hard to identify familiar constellations in a very dark sky: the tapestry of our night sky has an extremely deep hidden complexity. The featured composite reveals some of this complexity in a mosaic of 28 images taken over 800 hours from dark skies over Arizona, USA.

APOD: 2023 February 6 – In the Heart of the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. The featured image taken in mid-January using multiple exposures and very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), captures the central region in tremendous detail. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula's center measures about 50 light-years across, lies about 5,200 light-years away, and is visible with binoculars towards the constellation of the Unicorn (Monoceros).

APOD: 2021 March 22 - From Auriga to Orion
Explanation: What's up in the sky from Auriga to Orion? Many of the famous stars and nebulas in this region were captured on 34 separate images, taking over 430 hours of exposure, and digitally combined to reveal the featured image. Starting on the far upper left, toward the constellation of Auriga (the Chariot driver), is the picturesque Flaming Star Nebula (IC 405). Continuing down along the bright arc of our Milky Way Galaxy, from left to right crossing the constellations of the Twins and the Bull, notable appearing nebulas include the Tadpole, Simeis 147, Monkey Head, Jellyfish, Cone and Rosette nebulas. In the upper right quadrant of the image, toward the constellation of Orion (the hunter), you can see Sh2-264, the half-circle of Barnard's Loop, and the Horsehead and Orion nebulas. Famous stars in and around Orion include, from left to right, orange Betelgeuse (just right of the image center), blue Bellatrix (just above it), the Orion belt stars of Mintaka, Alnilam, and Alnitak, while bright Rigel appears on the far upper right. This stretch of sky won't be remaining up in the night very long -- it will be setting continually earlier in the evening as mid-year approaches.

APOD: 2021 February 21 - NGC 2244: A Star Cluster in the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. The featured image taken in January using multiple exposures and very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), captures the central region in tremendous detail. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula's center measures about 50 light-years across, lies about 5,200 light-years away, and is visible with binoculars towards the constellation of the Unicorn (Monoceros).

APOD: 2021 February 14 - Long Stem Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of this flowery emission nebula, at the top of the image, atop a long stem of glowing hydrogen gas. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of the Unicorn (Monoceros).

APOD: 2020 July 12 - Comet CG Creates Its Dust Tail
Explanation: Where do comet tails come from? There are no obvious places on the nuclei of comets from which the jets that create comet tails emanate. One of the best images of emerging jets is shown in the featured picture, taken in 2015 by ESA's robotic Rosetta spacecraft that orbited Comet 67P/Churyumov-Gerasimenko (Comet CG) from 2014 to 2016. The picture shows plumes of gas and dust escaping numerous places from Comet CG's nucleus as it neared the Sun and heated up. The comet has two prominent lobes, the larger one spanning about 4 kilometers, and a smaller 2.5-kilometer lobe connected by a narrow neck. Analyses indicate that evaporation must be taking place well inside the comet's surface to create the jets of dust and ice that we see emitted through the surface. Comet CG (also known as Comet 67P) loses in jets about a meter of radius during each of its 6.44-year orbits around the Sun, a rate at which will completely destroy the comet in only thousands of years. In 2016, Rosetta's mission ended with a controlled impact onto Comet CG's surface.

APOD: 2020 March 29 - A 212 Hour Exposure of Orion
Explanation: The constellation of Orion is much more than three stars in a row. It is a direction in space that is rich with impressive nebulas. To better appreciate this well-known swath of sky, an extremely long exposure was taken over many clear nights in 2013 and 2014. After 212 hours of camera time and an additional year of processing, the featured 1400-exposure collage spanning over 40 times the angular diameter of the Moon emerged. Of the many interesting details that have become visible, one that particularly draws the eye is Barnard's Loop, the bright red circular filament arcing down from the middle. The Rosette Nebula is not the giant red nebula near the top of the image -- that is a larger but lesser known nebula known as Lambda Orionis. The Rosette Nebula is visible, though: it is the red and white nebula on the upper left. The bright orange star just above the frame center is Betelgeuse, while the bright blue star on the lower right is Rigel. Other famous nebulas visible include the Witch Head Nebula, the Flame Nebula, the Fox Fur Nebula, and, if you know just where to look, the comparatively small Horsehead Nebula. About those famous three stars that cross the belt of Orion the Hunter -- in this busy frame they can be hard to locate, but a discerning eye will find them just below and to the right of the image center.

APOD: 2019 June 5 - The Interstellar Clouds of Orion
Explanation: The constellation of Orion is much more than three stars in a row. It is a direction in space that is rich with impressive nebulas. To better appreciate this well-known swath of sky, a new long exposure image was taken over several clear nights in January, February and March. After 23 hours of camera time and untold hours of image processing, the featured collage in the light of hydrogen, oxygen, and sulfur was produced spanning over 40 times the angular diameter of the Moon. Of the many interesting details that have become visible, one that particularly draws the eye is Barnard's Loop, the bright red orange arc just to the right of the image center. The Rosette Nebula is not the giant orange nebula just to the left of the image center -- that is larger but lesser known nebula known as the Meissa Ring. The Rosette Nebula is visible, though: it is the bright orange, blue and white nebula near the image bottom. The bright orange star just left of the frame center is Betelgeuse, while the bright blue star on the upper right is Rigel. About those famous three stars that cross the belt of Orion the Hunter -- in this busy frame they can be hard to locate, but a discerning eye will find them just to the right of the image center.

APOD: 2019 April 12 - A Cosmic Rose: The Rosette Nebula in Monoceros
Explanation: The Rosette Nebula, NGC 2237, is not the only cosmic cloud of gas and dust to evoke the imagery of flowers, but it is the most famous. At the edge of a large molecular cloud in Monoceros some 5,000 light years away, the petals of this cosmic rose are actually a stellar nursery. The lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young, O-type stars. Stars in the energetic cluster, cataloged as NGC 2244, are only a few million years young, while the central cavity in the Rosette Nebula, is about 50 light-years in diameter. The nebula can be seen with a small telescope toward the constellation of Monoceros, the Unicorn. This natural appearing telescopic portrait of the Rosette Nebula was made using broadband and narrowband filters, because sometimes roses aren't red.

APOD: 2018 October 8 - Comet 21P Between Rosette and Cone Nebulas
Explanation: Small bits of this greenish-gray comet are expected to streak across Earth's atmosphere tonight. Specifically, debris from the eroding nucleus of Comet 21P / Giacobini-Zinner, pictured, causes the annual Draconids meteor shower, which peaks this evening. Draconid meteors are easy to enjoy this year because meteor rates will likely peak soon after sunset with the Moon's glare nearly absent. Patience may be needed, though, as last month's passing of 21P near the Earth's orbit is not expected to increase the Draconids' normal meteor rate this year of (only) a few meteors per hour. Then again, meteor rates are notoriously hard to predict, and the Draconids were quite impressive in 1933, 1946, and 2011. Featured, Comet 21P gracefully posed between the Rosette (upper left) and Cone (lower right) nebulas two weeks ago before heading back out to near the orbit of Jupiter, to return again in about six and a half years.

APOD: 2018 February 22 - When Roses Aren't Red
Explanation: Not all roses are red of course, but they can still be very pretty. Likewise, the beautiful Rosette Nebula and other star forming regions are often shown in astronomical images with a predominately red hue, in part because the dominant emission in the nebula is from hydrogen atoms. Hydrogen's strongest optical emission line, known as H-alpha, is in the red region of the spectrum, but the beauty of an emission nebula need not be appreciated in red light alone. Other atoms in the nebula are also excited by energetic starlight and produce narrow emission lines as well. In this gorgeous view of the Rosette Nebula, narrowband images are combined to show emission from sulfur atoms in red, hydrogen in blue, and oxygen in green. In fact, the scheme of mapping these narrow atomic emission lines into broader colors is adopted in many Hubble images of stellar nurseries. The image spans about 100 light-years in the constellation Monoceros, at the 3,000 light-year estimated distance of the Rosette Nebula. To make the Rosette red, just follow this link or slide your cursor over the image.

APOD: 2017 March 14 - A Dark Winter Sky over Monfragüe National Park in Spain
Explanation: You, too, can see a night sky like this. That is because Monfragüe National Park in Spain, where this composite image was created, has recently had its night sky officially protected from potential future light pollution. Icons of the night sky that should continue to stand out during northern winter -- and are visible on the featured image -- include very bright stars like Sirius, Betelgeuse, and Procyon, bright star clusters like the Pleiades, and, photographically, faint nebulas like the California and Rosette Nebulas. Even 100 years ago, many people were more familiar with a darker night sky than people today, primarily because of the modern light pollution. Other parks that have been similarly protected as dark-sky preserves include Death Valley National Park (USA) and Grasslands National Park (Canada). Areas such as the city of Flagstaff, Arizona and much of the Big Island of Hawaii also have their night skies protected.

APOD: 2017 February 14 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of the Unicorn (Monoceros).

APOD: 2015 November 23 - A 212 Hour Exposure of Orion
Explanation: The constellation of Orion is much more than three stars in a row. It is a direction in space that is rich with impressive nebulas. To better appreciate this well-known swath of sky, an extremely long exposure was taken over many clear nights in 2013 and 2014. After 212 hours of camera time and an additional year of processing, the featured 1400-exposure collage spanning over 40 times the angular diameter of the Moon emerged. Of the many interesting details that have become visible, one that particularly draws the eye is Barnard's Loop, the bright red circular filament arcing down from the middle. The Rosette Nebula is not the giant red nebula near the top of the image -- that is a larger but lesser known nebula known as Lambda Orionis. The Rosette Nebula is visible, though: it is the red and white nebula on the upper left. The bright orange star just above the frame center is Betelgeuse, while the bright blue star on the lower right is Rigel. Other famous nebulas visible include the Witch Head Nebula, the Flame Nebula, the Fox Fur Nebula, and, if you know just where to look, the comparatively small Horsehead Nebula. About those famous three stars that cross the belt of Orion the Hunter -- in this busy frame they can be hard to locate, but a discerning eye will find them just below and to the right of the image center.

APOD: 2015 February 25 - The Rosette Nebula in Hydrogen and Oxygen
Explanation: The Rosette Nebula is not the only cosmic cloud of gas and dust to evoke the imagery of flowers -- but it is the most famous. At the edge of a large molecular cloud in Monoceros, some 5,000 light years away, the petals of this rose are actually a stellar nursery whose lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young stars. The stars in the energetic cluster, cataloged as NGC 2244, are only a few million years old, while the central cavity in the Rosette Nebula, cataloged as NGC 2237, is about 50 light-years in diameter. The nebula can be seen firsthand with a small telescope toward the constellation of the Unicorn (Monoceros).

APOD: 2014 March 11 - In the Heart of the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. The above image taken in January using multiple exposures and very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), captures the central region in tremendous detail. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula's center measures about 50 light-years across, lies about 4,500 light-years away, and is visible with binoculars towards the constellation of the Unicorn (Monoceros).

APOD: 2012 February 14 - The Rosette Nebula
Explanation: The Rosette Nebula is not the only cosmic cloud of gas and dust to evoke the imagery of flowers -- but it is the most famous. At the edge of a large molecular cloud in Monoceros, some 5,000 light years away, the petals of this rose are actually a stellar nursery whose lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young stars. The stars in the energetic cluster, cataloged as NGC 2244, are only a few million years old, while the central cavity in the Rosette Nebula, cataloged as NGC 2237, is about 50 light-years in diameter. The nebula can be seen firsthand with a small telescope toward the constellation of the Unicorn (Monoceros).

APOD: 2011 February 21 - Milky Way Over Switzerland
Explanation: What's visible in the night sky during this time of year? To help illustrate the answer, a beautiful land, cloud, and skyscape was captured earlier this month over Neuchâtel, Switzerland. Visible in the foreground were the snow covered cliffs of the amphitheater shaped Creux du Van, as well as distant trees, and town-lit clouds. Visible in the night sky (at midnight) were galaxies including the long arch of the central band of our Milky Way Galaxy, the Andromeda galaxy (M31), and the Triangulum galaxy (M33). Star clusters visible included NGC 752, M34, M35, M41, the double cluster, and the Beehive (M44). Nebulas visible included the Orion Nebula (M42), NGC 7822, IC 1396, the Rosette Nebula, the Flaming Star Nebula, the California Nebula, the Heart and Soul Nebulas, and the Pacman Nebula. Rolling your cursor over the above image will bring up labels for all of these. But the above wide angle sky image captured even more sky wonders. What other nebulas can you find in the above image?

APOD: 2011 February 14 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of the Unicorn (Monoceros).

APOD: 2010 February 14 - Field of Rosette
Explanation: What surrounds the florid Rosette nebula? To better picture this area of the sky, the famous flowery emission nebula on the far right has been captured recently in a deep and dramatic wide field image that features several other sky highlights. Designated NGC 2237, the center of the Rosette nebula is populated by the bright blue stars of open cluster NGC 2244, whose winds and energetic light are evacuating the nebula's center. Below the famous flower, a symbol of Valentine's Day, is a column of dust and gas that appears like a rose's stem but extends hundreds of light years. Across the above image, the bright blue star just left and below the center is called S Monocerotis. The star is part of the open cluster of stars labelled NGC 2264 and known as the Snowflake cluster. To the right of S Mon is a dark pointy featured called the Cone nebula, a nebula likely shaped by winds flowing out a massive star obscured by dust. To the left of S Mon is the Fox Fur nebula, a tumultuous region created by the rapidly evolving Snowflake cluster. The Rosette region, at about 5,000 light years distant, is about twice as far away as the region surrounding S Mon. The entire field can be seen with a small telescope toward the constellation of the Unicorn (Monoceros).

APOD: 2009 December 2 - Dust Sculptures in the Rosette Nebula
Explanation: What creates the cosmic dust sculptures in the Rosette Nebula? Noted for the common beauty of its overall shape, parts of the Rosette Nebula, also known as NGC 2237, show beauty even when viewed up close. Visible above are globules of dark dust and gas that are slowly being eroded away by the energetic light and winds by nearby massive stars. Left alone long enough, the molecular-cloud globules would likely form stars and planets. The above image was taken in very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue). The Rosette Nebula spans about 50 light-years across, lies about 4,500 light-years away, and can be seen with a small telescope towards the constellation of the Unicorn (Monoceros).

APOD: 2009 April 11 - The Big Picture
Explanation: Intricate, glowing nebulae that shine in planet Earth's night sky are beautiful to look at in deep images made with telescopes and sensitive cameras. But they are faint and otherwise invisible to the naked-eye. That makes their relative location and extent on the sky difficult to appreciate. So, consider this impressive composite image of a wide region of the northern winter sky. With a total exposure time of 40 hours, the painstaking mosaic presents a nebula-rich expanse known as the Orion-Eridanus Superbubble above a house in suburban Boston, USA. Within the wide and deep view are nebulae more often seen in narrower views, including the Great Orion Nebula, the Rosette Nebula, the Seagull Nebula, the California Nebula, and Barnard's Loop. The familiar constellation of Orion itself is just above the foreground house. Brightest star Sirius is left of the roof, and the recognizable Pleiades star cluster is above the tree at the right. A version of the big picture that includes simple constellation guidelines is available here.

APOD: 2008 February 14 - Long Stem Rosette
Explanation: The Rosette Nebula (aka NGC 2237) is not the only cosmic cloud of gas and dust to evoke the imagery of flowers. But it is the one most often suggested as a suitable astronomy image for Valentine's Day. Of the many excellent Rosette Nebula pictures submitted to APOD editors, this view seemed most appropriate, with a long stem of glowing hydrogen gas in the region included in the composition. At the edge of a large molecular cloud in Monoceros, some 5,000 light years away, the petals of this rose are actually a stellar nursery whose lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young stars. The stars in the energetic cluster, cataloged as NGC 2244, are only a few million years old, while the central cavity in the Rosette Nebula is about 50 light-years in diameter. Happy Valentine's Day!

APOD: 2007 July 26 - Hot Stars in the Rosette Nebula
Explanation: Winds and radiation from massive hot stars in the Rosette Nebula have cleared the natal gas and dust from the center of the nearby star-forming region. They also pose a danger to planet forming disks around young, cooler stars in the neighborhood. This Spitzer Space Telescope infrared image of dust clouds near the Rosette's central region, shows the cleared-out cavity. The view spans about 45 light-years at the the nebula's estimated distance of 5,200 light-years. Putting your cursor over the false color picture will highlight the dangerous hot stars, classified as O stars with surface temperatures of 25,000 kelvins or higher. Astronomers calculate that cool stars wandering within about 1.6 light-years of the Rosette's O stars are in danger of having their planet forming disks destroyed.

APOD: 2007 June 6 - Dust Sculptures in the Rosette Nebula
Explanation: What creates the cosmic dust sculptures in the Rosette Nebula? Noted for the common beauty of its overall shape, parts of the Rosette Nebula, also known as NGC 2244, show beauty even when viewed up close. Visible above are globules of dark dust and gas that are slowly being eroded away by the energetic light and winds by nearby massive stars. Left alone long enough, the molecular-cloud globules would likely form stars and planets. The above image was taken in very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue). The Rosette Nebula spans about 50 light-years across, lies about 4,500 light-years away, and can be seen with a small telescope towards the constellation of the Unicorn (Monoceros).

APOD: 2007 February 14 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of Monoceros.

APOD: 2006 March 24 - When Roses Aren't Red
Explanation: Not all roses are red of course, but they can still be very pretty. Likewise, the beautiful Rosette Nebula and other star forming regions are often shown in astronomical images with a predominately red hue - in part because the dominant emission in the nebula is from hydrogen atoms. Hydrogen's strongest optical emission line, known as H-alpha, is in the red region of the spectrum, but the beauty of an emission nebula need not be appreciated in red light alone. Other atoms in the nebula are also excited by energetic starlight and produce narrow emission lines as well. In this gorgeous view of the Rosette's central regions, narrow band images are combined to show emission from sulfur atoms in red, hydrogen in blue, and oxygen in green. In fact, the scheme of mapping these narrow atomic emission lines into broader colors is adopted in many Hubble images of stellar nurseries. This image spans about 50 light-years in the constellation Monoceros, at the 3,000 light-year estimated distance of the Rosette Nebula.

APOD: 2006 February 14 - Dust and Light in the Rosette Nebula
Explanation: What creates the cosmic dust sculptures in the Rosette Nebula? Noted for the common beauty of its overall shape, parts of the Rosette Nebula, also known as NGC 2244, show beauty even when viewed up close. Visible above are globules of dark dust and gas that are slowly being eroded away by the energetic light and winds by nearby massive stars. Left alone long enough, the molecular-cloud globules would likely form stars and planets. The Rosette Nebula spans about 50 light-years across, lies about 4,500 light-years away, and can be seen with a small telescope towards the constellation of Monoceros. Happy Valentine's Day from the folks at APOD.

APOD: 2005 December 23 - Hydrogen and Dust in the Rosette Nebula
Explanation: At the edge of a large molecular cloud in Monoceros, some 3,000 light years away, dark filaments of dust are silhouetted by luminous hydrogen gas. The close up view of the Rosette Nebula dramatically suggests that star formation is an on going process in the region, with dark filaments sculpted by winds and radiation from hot, young stars. Ultraviolet radiation from the young stars also strips electrons from the surrounding hydrogen atoms. As electrons and atoms recombine they emit longer wavelength, lower energy light in a well known characteristic pattern of bright spectral lines. At visible wavelengths, the strongest emission line in this pattern is in the red part of the spectrum and is known as "Hydrogen-alpha" or just H-alpha. Part of IPHAS, a survey of H-alpha emission in our Milky Way Galaxy, this image spans about 25 light-years.

APOD: 2005 April 19 - Orion in Infrared
Explanation: Do you recognize the constellation Orion? This striking but unfamiliar looking picture of the familiar Orion region of the sky was produced using survey data from the now-defunct InfraRed Astronomical Satellite (IRAS). The above image combines information recorded at three different invisible infrared wavelengths and covers about 30x24 degrees on the sky. Most of Orion's visually impressive stars don't stand out, but bright Betelgeuse does appear as a small bright purplish dot on the lower left. The bright region on the right contains the Great Nebula in Orion, while the bright region just above the image bottom is the Rosette Nebula. Surrounding these regions are a jumble of chaotic glowing gas and dark dust jettisoned by stars forming and exploding over millions of years.

APOD: 2005 February 14 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of Monoceros.

APOD: 2005 January 10 - Dust Sculptures in the Rosette Nebula
Explanation: What creates the cosmic dust sculptures in the Rosette Nebula? Noted for the common beauty of its overall shape, parts of the Rosette Nebula, also known as NGC 2244, show beauty even when viewed up close. Visible above are globules of dark dust and gas that are slowly being eroded away by the energetic light and winds by nearby massive stars. Left alone long enough, the molecular-cloud globules would likely form stars and planets. The above image was taken in very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue). The Rosette Nebula spans about 50 light-years across, lies about 4,500 light-years away, and can be seen with a small telescope towards the constellation of Monoceros.

APOD: 2003 April 29 - In the Center of the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. This just-released image taken by the CFHT's new MegaPrime camera shows the region in unprecedented detail. Although the emission nebula is dominated by red hydrogen light, the above image has exaggerated the effect of green light emitted primarily by small amounts of oxygen. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula's center measures about 50 light-years across, lies about 4500 light-years away, and is visible with binoculars towards the constellation of Monoceros.

APOD: 2003 April 4 - Clusters and Nebulae of the Hexagon
Explanation: At first, the bright stars of the large asterism known as the (northern) Winter Hexagon might be hard to pick out in this gorgeous deep sky mosaic from December 2002. But placing your cursor over the picture will reveal the hexagon's outlines and the bright clusters and nebulae along a stunning portion of the Milky Way opposite the galactic center. The celestial highlights include M42 (aka the Great Nebula of Orion), Orion's Horsehead nebula, the Rosette and Cone nebulae, and nearby star clusters M45 (Pleiades) and Gemini's own M35. For now, this hexagon is sinking low in western evening skies.

APOD: 2002 March 17 - NGC 2244: A Star Cluster in the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only four million years ago and emit light and wind that define the nebula's appearance today. High energy light from the bright young stars of NGC 2244 ionizes the surrounding hydrogen gas clouds to create the red emission nebula appearance. The hot wind of particles that streams away from the cluster stars contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. NGC 2244 measures about 50 light-years across, lies about 4500 light-years away, and is visible with binoculars towards the constellation of Monoceros.

APOD: 2001 October 19 - X-Ray Stars and Winds in the Rosette Nebula
Explanation: This mosaic of x-ray images cuts a swath across the photogenic Rosette Nebula, a stellar nursery 5,000 light-years from Earth in the constellation Monoceros, the Unicorn. Constructed from data recorded by the orbiting Chandra X-ray Observatory, the mosaic spans less than 100 light-years and is color coded to show low energies in red and high energy x-rays in blue. At the upper right is the young star cluster NGC 2244, central to the Rosette Nebula itself. The hot outer layers of the massive stars are seen to be copious sources of x-rays, but a diffuse x-ray glow also pervades this cluster of newborn stars. Since these stars are so young (less than few million years old!) the diffuse x-ray emission is thought to be powered by energetic, colliding stellar winds rather than remnants of supernovae explosions, a final act in the life cycle of a massive star. Moving away from the center, south and east across the nebula (upper right to lower left), the hot, blustery environment gives way to dense molecular gas, absorbing low energy x-rays while revealing the penetrating high energy x-rays from embedded stars.

APOD: 2001 February 14 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars formed about four million years ago from the nebular material and their stellar winds are clearing a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow. The Rosette Nebula spans about 100 light-years across, lies about 5000 light-years away, and can be seen with a small telescope towards the constellation of Monoceros.

APOD: 2000 August 22 - NGC 2244: A Star Cluster in the Rosette Nebula
Explanation: In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only four million years ago and emit light and wind that define the nebula's appearance today. High energy light from the bright young stars of NGC 2244 ionizes the surrounding hydrogen gas clouds to create the red emission nebula appearance. The hot wind of particles that streams away from the cluster stars contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. NGC 2244 measures about 50 light-years across, lies about 4500 light-years away, and is visible with binoculars towards the constellation of Monoceros.

APOD: 2000 January 11 - The Rosette Nebula in Hydrogen, Oxygen, and Sulfur
Explanation: The Rosette Nebula is a large emission nebula located 3000 light-years away. The great abundance of hydrogen gas gives NGC 2237 its red color in most photographs. The wind from the open cluster of stars known as NGC 2244 has cleared a hole in the nebula's center. The above photograph, however, was taken in the light emitted by three elements of the gas ionized by the energetic central stars. Here green light originating from oxygen and blue light originating from sulfur supplements the red from hydrogen. Filaments of dark dust lace run through the nebula's gases. The origin of recently observed fast-moving molecular knots in the Rosette Nebula remains under investigation.

APOD: November 26, 1998 - Meteor Milky Way
Explanation: The bold, bright star patterns of Orion (right) are a familiar sight to even casual skygazers. But this gorgeous color photo also features a subtler spectacle - the faint stars of the Milky Way. A broad region of the Milky Way runs vertically through the picture with the striking red Rosette Nebula in bloom left of center. Cutting across this dim, diffuse band of stars which lie along the plane of our Galaxy is a meteor streak. It seems to pass just under the red-orange giant star Betelgeuse at Orion's shoulder. Astrophotographer Jeff Medkeff recorded this and other beautiful time exposures from a dark sky countryside southeast of Sierra Vista, Arizona USA, during November's Leonid meteor shower.

APOD: February 14, 1998 - The Rosette Nebula
Explanation: Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars recently formed from the nebular material and their stellar "wind" has cleared a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow.

APOD: May 22, 1996 - Star Cluster in the Rosette Nebula
Explanation: Embedded in the center of the colorful and photogenic Rosette Nebula is a bright, young open cluster. The bright blue stars in this cluster, labelled NGC 2244, emit ultraviolet light that knocks electrons away from hydrogen atoms. When the electrons fall back, they emit the red light which distinctively defines the glow of all emission nebulae. The Rosette Nebula is thousands of light years distant, but light would take only about 100 years to cross it. The Rosette Nebula is not difficult to observer and, although faint, actually appears larger than the full moon.

APOD: February 14, 1996 - NGC 2237: The Rosette Nebula
Explanation: Would the Rosette nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244. These stars recently formed from the nebular material and their stellar "wind" has cleared a hole in the nebula's center, insulated by a layer of dust and hot gas. Ultraviolet light from the hot cluster stars causes the surrounding nebula to glow.