New Comets, Asteroids Discovered by NASA (PHOTOS)

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Zeta Ophiuchi -- Runaway Star Plowing Through Space Dust

The blue star near the center of this image is Zeta Ophiuchi. Zeta Ophiuchi is actually a very massive, hot, bright blue star plowing its way through a large cloud of interstellar dust and gas. Astronomers theorize that this stellar juggernaut was likely once part of a binary star system with an even more massive partner. It's believed that when the partner exploded as a supernova, blasting away most of its mass, Zeta Ophiuchi was suddenly freed from its partner's pull and shot away like a bullet moving 24 kilometers per second (54,000 miles per hour). Zeta Ophiuchi is about 20 times more massive and 65,000 times more luminous than the sun. If it weren't surrounded by so much dust, it would be one of the brightest stars in the sky and appear blue to the eye. It's already about halfway through its very short 8-million-year lifespan. In comparison, the sun is roughly halfway through its 10-billion-year lifespan. While the sun will eventually become a quiet white dwarf, Zeta Ophiuchi, like its ex-partner, will ultimately die in a massive explosion called a supernova. The most interesting features in this image are related to the interstellar gas and dust that surrounds Zeta Ophiuchi. Another interesting feature is the bright yellow curved thing directly above Zeta Ophiuchi.

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Dancing Galaxies

This image features two stunning galaxies engaged in an intergalactic dance. The galaxies, Messier 81 and Messier 82, swept by each other a few hundred million years ago, and will likely continue to twirl around each other multiple times before eventually merging into a single galaxy. The relatively recent encounter triggered a spectacular burst of star formation visible in both galaxies. Messier 81 (bottom of image) is a prototypical "grand design" spiral galaxy with its pronounced and well-defined arms spiraling into its core. Messier 82 (top of image) is also a spiral galaxy. However, it is seen edge-on from our point of view. A third, smaller galaxy, NGC 3077, can be seen at lower left. This spiral galaxy belongs to the same group as Messier 81 and Messier 82 -- a group that includes at least a dozen gravitationally linked galaxies. NGC 3077 is also experiencing a burst of new star birth, likely triggered by its interaction with Messier 81.

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Galaxy For Everyone

NASA's Wide-Field Infrared Explorer, or WISE, the mission team has put together this image showing just a sample of the millions of galaxies that have been imaged by WISE during its survey of the entire sky. NGC 300 is seen in the image in the upper left panel. This is a textbook spiral galaxy. At about 39,000 light-years across, NGC 300 is only about 40 percent the size of the Milky Way galaxy. The upper right image shows Messier 104, or M104, also known as the Sombrero galaxy. Although M104 is also classified as a spiral galaxy, it has a very different appearance than NGC 300. In part, this is because the dusty, star-forming spiral disk in M104 is seen nearly edge-on from our point of view. M104 also has a large, ball-shaped bulge component of older stars, seen here in blue. The large, fuzzy grouping of stars at the center of the lower left panel is the galaxy Messier 60, or M60. This galaxy does not have a spiral disk, just a bulge, making it a massive elliptical galaxy. M60 is about 20 percent larger than the Milky Way galaxy, and lies in the Virgo cluster of galaxies. The brighter dense spot inside but off-center from the blue core of M60 is a separate spiral galaxy called NGC 4647. Recent evidence suggests there is a black hole at the center of M60 with a mass of about 4.5 billion times that of the sun, making it one of the largest black holes known. The galaxy in the lower right panel is Messier 51, or NGC 5194, also frequently referred to as the Whirlpool galaxy. The Whirlpool is a "grand design" spiral galaxy. It is interacting with its smaller companion -- NGC 5195, a dwarf galaxy, which can be seen as a bright spot near the tip of the spiral arm extending up and to the right of the larger galaxy. The Whirpool's very bright spiral arms show areas of compressed dust and gas.

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Explosion of Infrared Light

A circular rainbow appears like a halo around an exploded star in this new view of the IC 443 nebula from NASA's Wide-field Infrared Survey Explorer, or WISE. When massive stars die, they explode in tremendous blasts, called supernova, which send out shock waves. The shock waves sweep up and heat surrounding gas and dust, creating supernova remnants like the one pictured here. The supernova in IC 443 happened somewhere between 5,000 and 10,000 years ago. In this WISE image, infrared light has been color-coded to reveal what our eyes cannot see. The colors differ primarily because materials surrounding the supernova remnant vary in density. When the shock waves hit these materials, different gases were triggered to release a mix of infrared wavelengths. IC 443 can be found near the star Eta Geminorum, which lies near Castor, one of the twins in the constellation Gemini.

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Lagoon Nebula

This colorful picture is a mosaic of the Lagoon nebula taken by NASA's Wide-field Infrared Survey Explorer, or WISE. Normally, you would expect a lagoon to be filled with water, but this nebula is composed of clouds of gas and dust in which new stars are forming. Also known as Messier 8, or simply M8, the Lagoon nebula is seen here as a large circular cloud in the center of the image, surrounded by innumerable stars. Lagoon nebula can be found in constellation Sagittarius. Distance measurements to this nebula vary widely, from 4,000 to 6,500 light-years away from Earth. At the center of the Lagoon nebula is the star Herschel 36. M8 is a favorite target for amateur astronomers because it can be easily seen with binoculars or a small telescope. Astronomers have identified several different parts of the Lagoon nebula, including M8E, a young stellar object, and the star clusters NGC 6523 and NGC 6530.

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Neighbor Galaxy

This image shows of one of our closest neighboring galaxies, Messier 33. Also named the Triangulum galaxy (after the constellation it's found in), M33 is one of largest members in our small neighborhood of galaxies -- the Local Group. The Local Group consists of about 30 galaxies that are gravitationally bound and travel together through the universe. M33 is the third largest member of the Local Group, dwarfed only by the Andromeda galaxy (M31) and our very own home galaxy, the Milky Way. M33 is extremely close as far as galaxies go, residing only 3 million light-years away. Star-forming regions are easy to spot in infrared (green and red areas in this image). The bright yellow-orange 'blobs' scattered throughout M33 are areas where stars are forming at an especially intense rate. The largest one in the spiral arm to the upper left has its own name, NGC 604.

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Chasing Chickens in Lambda Centauri Nebula

This infrared image from WISE shows the Lambda Centauri nebula, a star-forming cloud in our Milky Way galaxy, also known as the Running Chicken nebula. The nebula, cataloged as IC 2944, is about 5,800 light-years from Earth and is home to a new cluster of stars born from the cloud nearly 8 million years ago. The hottest members of the cluster produce enough ultraviolet radiation and strong winds to convert the cloud into ions and excavate it. The ionized gas glows in visible light, but in infrared light we see the dust in the cloud warmed by the very same radiation. The red, glowing dust is the coolest material visible in this image and is composed of metallic dust grains. The greenish components in the image are warmer dust grains composed of smog-like materials. The large green ring-like structure near the middle of the image is some 77 light-years across and was formed when materials that created the stars in the clusters were blown back by the combined winds of the stars. The nebula gets its common name because in some visible light images it resembles a running chicken. It is also called the Lambda Centauri nebula because it appears to surround the bright star Lambda Centauri. Lambda Centauri is one of the brightest stars in the constellation Centaurus.

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Cosmic Cocoon

The aptly named Cocoon nebula is featured in this image from NASA's Wide-field Infrared Survey Explorer, or WISE. This cloud of dust and gas, cataloged as IC 5416 and located in the constellation Cygnus, is wrapped in a dark cloud of dust called Barnard 168. Within this cocoon of dust and gas, new stars are forming and beginning to emerge into the wild. In the heart of the nebula, which looks surprisingly like a Valentine's heart in WISE's view, massive new stars are emerging. The intense radiation from these stars heats up the cloud. The highest-energy light from the stars rips electrons from hydrogen atoms, which then recombine with the atoms and emit visible light. The dusty cocoon extends over 45 light-years across, which is more than three times larger than the inner, glowing portion of the nebula.

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The Dark Heart of the King

WISE captured this image of a hidden star-forming cloud of dust and gas located in the constellation of Cepheus. Cepheus, father of Andromeda, was a mythological king in the ancient Greek world. This image of dark nebulae lies near the heart of the king, as imagined by ancient Greek astronomers. The dust in these nebulae blocks visible light passing through, and the cloud and its contents are mostly hidden when viewed in visible light. The central portion is known as IRAS 22298+6505. IRAS stands for Infrared Astronomical Satellite, a predecessor to WISE and an international satellite that mapped the sky in infrared light in the 1980s. Other portions of this cloud are called TGU H686 P2 and LDN 1213. As with IRAS, the first letters of these objects refer to astronomical catalogs. What looked like distinct nebulae in those surveys are revealed as a much larger cloud complex by WISE. This complex spans about 120 light-years across and is located about 2,500 light-years away at the edge of a spiral arm of the Milky Way galaxy, called the Orion spur.

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A Spiral Galaxy is Visited by a Trojan War Hero

It's a bird! It's a plane! Nope, it's an asteroid tracking its way across the sky with a beautiful spiral galaxy in the background. In the center of this new mosaic image captured by NASA's Wide-field Infrared Survey Explorer (WISE) is the galaxy Messier 74, with its spiral arms seen face-on. The bright reddish object moving across the lower right part of the image is the much closer asteroid 3540 Protesilaos, seen at different points in its orbit around the sun. Also known as NGC 628, the Messier 74 galaxy is between 24.5 and 36 million light-years away, and has a diameter of about 100,000 light-years. It is suspected to have a black hole at its center, with a mass equal to 10,000 suns. By convention, Trojan asteroids are named after the heroes from the Trojan War. In this case, asteroid 3540 is named after the hero Protesilaos. According to Greek mythology, Protesilaos was the first Greek to set foot on Trojan land during the war. Unfortunately for him, there was a prophecy that the first soldier in the war to step onto land from a battle ship would die. The prophecy quickly came true and Protesilaos was killed.