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Sky Survey Captures the Universe By Maia Weinstock Staff Writer posted: 07:00 am ET 20 July 2000
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2MASS Image Gallery
The Two-Micron All Sky Survey, or 2MASS for short, has returned a flood of data from the skies, including images of millions of stars and galaxies. In fact, the most recent release of 2MASS data covers almost half of the sky and unleashes the most eye-catching near-infrared images to date. SPACE.com proudly presents some of the most interesting and spectacular of this latest batch. The Tarantula Nebula is a faint patch of light located some 160,000 light-years away from Earth in the Large Magellenic Cloud, the nearest galaxy to our native Milky Way galaxy. This is the only nebula outside the Milky Way that can be seen with the naked eye. At the core of the nebula lies a dense clump of hot stars, which until recently were thought to be one massive star.
Scientists say this galaxy, dubbed NGC 891, is very similar to our own Milky Way galaxy. Though we can't see its complete form due to its oblique angle relative to Earth, researchers have shown that the galaxy is rather thin - a likely characteristic shared by the Milky Way. We also know that the galaxy's disk is composed of dust and light from supergiant stars, and is located about 30 million light-years away. The Flame Nebula, also known as the Christmas Tree Nebula, is an area of gas and dust located in the constellation Orion. Scientists say that this dense stellar cluster contains a great many young stars and disks of accreting material, which may be sites of planet formation. This cluster is thought to be less than one million years old. This image features a young star cluster known as K3-50. Located 28,000 light-years away in the constellation Cygnus, K3-50 is between 10,000 and 100,000 years old - quite young in comparison with our star, the sun, which is about 5 billion years old. Scientists say that at least three of the stars in this cluster are more than 60 times more massive than our sun. The two galaxies seen here, NGC 5194 and NGC 5195, are known together as the Whirlpool Nebula. Relatively near neighbors, the pair lies some 9 million light-years from the Milky Way galaxy. The larger galaxy is about 400 million years old and has a mass of about 40 million times that of our sun. This 2MASS image is the first known near-infrared image of this object, which appears to be a region of massive star formation. Known as IRAS 20306+4005, the object has not been well studied. However, in this image you can see filaments of gas surrounding young stars can be seen embedded in the dusty cloud in which they formed. A member of the constellation Coma Berenices, M 99 is a bright galaxy in the Virgo Cluster of galaxies, of which the Milky Way is also a part. A clockwise-rotating galaxy, M99 is unusually asymmetric. At a distance of 60 million light-years, M99 is speeding through the Virgo Cluster at about 745 miles (1,200 kilometers) per second. This mosaic image, which contains more than 1 million stars, shows the galactic plane of the Milky Way galaxy. Because it "sees" in the near-infrared, 2MASS was able to glimpse through obscuring dust that lies between Earth and the Milky Way's center. The very center of the galaxy (about 26,400 light-years away from Earth) can be seen as the reddish area of this image. The Sombrero Galaxy, M 104, looks eerily like a Mexican sombrero hat - hence, its nickname. Scientists say the glow associated with the central bulge of this galaxy is due to the presence of billions of old stars. The rings, on the other hand, harbor many younger, brighter stars. The Sombrero Galaxy lies some 50 million light-years from Earth in the constellation Virgo. Scientists say that the pinkish color in the bright ring of this nebula, dubbed NGC 6369, may be due to emissions by hydrogen in the area. Visible with a good telescope in the constellation of Ophiuchus, the ring is composed of gas that has been expelled by the nebula's main star. Though hard to tell from this photo, this nebula is interesting in that its "central" star is located slightly closer to one edge than the others. Like stars, galaxies often form close groups--systems that contain typically tens or hundreds of galaxies. Often, the galaxies in tight groups are slowly merging or pulling away from each other. The group in this image is called Hickson 40, and it's located near the constellation Hydra, about 300 million light-years away from Earth. This is an image of a molecular cloud and embedded star cluster called Monoceros R 2, or Mon R 2 for short. Scientists say that the Mon R 2 cluster is one of the nearest massive star-forming regions they know of that remains embedded in a molecular cloud. At a distance of 2700 light-years away, Mon R 2 likely formed sometime in the past few million years. The Ring Nebula, one of the most famous and stunning celestial objects, is about one light-year across and lies 2,000 light-years away in the northern constellation Lyra. Officially known as M 57, this planetary nebula is about 1 light-year in diameter. The Trifid Nebula, also known as M 20, is located in the constellation Sagittarius and lies about 6,500 light-years away. This nebula is named for three dark lines of dust that split it into smaller "pieces." This infrared image allows astronomers to see through these dust lines, which are obscure observations in the optical-light range. The nebula is about 20 light-years across. The Orion Nebula is one of the more well-studied nebulae in our local vicinity. A huge stellar nursery, the nebula is a relatively close neighbor - it lies 1,500 light-years from Earth, in the same spiral arm of the Milky Way as the solar system. It can be easily seen in the night sky as the middle "star" in the sword of Orion, the Hunter. This mosaic shows the galaxy NGC 205, also known as M 110. This galaxy is a companion to the famous giant spiral of the Andromeda Galaxy (M 31). Astronomers first thought NGC 205 was quite old, but they later realized it hosts dust clouds and relatively young stars. Scientists estimate that much of the star formation in the galaxy took place over the last 100 million years.
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