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In August of 1999, NASA released an image of Cassiopeia A, a supernova remnant revealed in never-before-seen X-ray detail. The "Cas A" image, as it has come to be known, shows remarkable structure in the debris of a gigantic stellar explosion, as well as an enigmatic source in the center, which could be a rapidly spinning neutron star or black hole. The Chandra X-ray Observatory image of Cas A ushered in a new era of X-ray astronomy. This image was produced from the archives to celebrate the anniversary of Chandra’s first light. The low, medium, and higher X-ray energies of the Chandra data are shown as red, green, and blue respectively.

NASA's Chandra X-ray Observatory has captured a spectacular image of G292.0+1.8, a young, oxygen-rich supernova remnant with a pulsar at its center surrounded by outflowing material. Astronomers know that pulsars are formed in supernova explosions, but they are currently unable to identify what types of massive stars must die in order for a pulsar to be born. Now that Chandra has revealed strong evidence for a pulsar in G292.0+1.8, astronomers can use the pattern of elements seen in the remnant to make a much closer connection between pulsars and the massive stars from which they form. This Chandra image shows a rapidly expanding shell of gas that is 36 light years across and contains large amounts of elements such as oxygen, neon, magnesium, silicon and sulfur. Embedded in this cloud of multimillion degree gas is a key piece of evidence linking neutron stars and supernovas produced by the collapse of massive stars.

In this unusual image, NASA’s Hubble Space Telescope captures a rare view of the celestial equivalent of a geode -- a gas cavity carved by the stellar wind and intense ultraviolet radiation from a hot young star. Real geodes are baseball-sized, hollow rocks that start out as bubbles in volcanic or sedimentary rock. Only when these inconspicuous round rocks are split in half by a geologist, do we get a chance to appreciate the inside of the rock cavity that is lined with crystals. In the case of Hubble's 35 light-year diameter "celestial geode" the transparency of its bubble-like cavity of interstellar gas and dust reveals the treasures of its interior.

Astronomers may not have observed the fabled "Stairway to Heaven," but they have photographed something almost as intriguing: ladder-like structures surrounding a dying star. A new image, taken with NASA's Hubble Space Telescope, reveals startling new details of one of the most unusual nebulae known in our Milky Way. Cataloged as HD 44179, this nebula is more commonly called the "Red Rectangle" because of its unique shape and color as seen with ground-based telescopes.

Resembling a diamond-encrusted bracelet, a ring of brilliant blue star clusters wraps around the yellowish nucleus of what was once a normal spiral galaxy in this new image from NASA's Hubble Space Telescope (HST). This image is being released to commemorate the 14th anniversary of Hubble's launch on April 24, 1990 and its deployment from the space shuttle Discovery on April 25, 1990. The galaxy, cataloged as AM 0644-741, is a member of the class of so-called "ring galaxies." It lies 300 million light-years away in the direction of the southern constellation Volans.

This image resembling Vincent van Gogh's painting, "Starry Night," is Hubble's latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon). This Hubble image was obtained with the Advanced Camera for Surveys on February 8, 2004. The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light two years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy.

Seventeen years ago, astronomers spotted the brightest stellar explosion ever seen since the one observed by Johannes Kepler 400 years ago. Called SN 1987A, the titanic supernova explosion blazed with the power of 100,000,000 suns for several months following its discovery on Feb. 23, 1987. Although the supernova itself is a million times fainter than 17 years ago, a new light show in the space surrounding it is just beginning.

This image, taken Nov. 28, 2003 by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope, shows many bright spots along a ring of gas, like pearls on a necklace. These cosmic "pearls" are being produced as a supersonic shock wave unleashed during the explosion slams into the ring at more than a million miles per hour. The collision is heating the gas ring, causing its innermost regions to glow. Curiously, one of the bright spots on the ring [at 4 o'clock] is a star that happens to lie along the telescope's line of sight.

NASA's Hubble Space Telescope has trained its razor-sharp eye on one of the universe's most stately and photogenic galaxies, the Sombrero galaxy, Messier 104 (M104). The galaxy's hallmark is a brilliant white, bulbous core encircled by the thick dust lanes comprising the spiral structure of the galaxy. As seen from Earth, the galaxy is tilted nearly edge-on. We view it from just six degrees north of its equatorial plane. This brilliant galaxy was named the Sombrero because of its resemblance to the broad rim and high-topped Mexican hat.

Resembling the puffs of smoke and sparks from a summer fireworks display in this image from NASA's Hubble Space Telescope, these delicate filaments are actually sheets of debris from a stellar explosion in a neighboring galaxy. Hubble's target was a supernova remnant within the Large Magellanic Cloud (LMC), a nearby, small companion galaxy to the Milky Way visible from the southern hemisphere.

Resembling the fury of a raging sea, this image actually shows a bubbly ocean of glowing hydrogen gas and small amounts of other elements such as oxygen and sulfur.

The photograph, taken by NASA's Hubble Space Telescope, captures a small region within M17, a hotbed of star formation. M17, also known as the Omega or Swan Nebula, is located about 5,500 light-years away in the constellation Sagittarius. The image is being released to commemorate the thirteenth anniversary of Hubble's launch on April 24, 1990.

In January 2002, a dull star in an obscure constellation suddenly became 600,000 times more luminous than our Sun, temporarily making it the brightest star in our Milky Way galaxy. The mysterious star, called V838 Monocerotis, has long since faded back to obscurity. But observations by NASA's Hubble Space Telescope of a phenomenon called a "light echo" around the star have uncovered remarkable new features. These details promise to provide astronomers with a CAT-scan-like probe of the three- dimensional structure of shells of dust surrounding an aging star.

Just when it seemed like the summer movie season had ended, two of NASA's Great Observatories have produced their own action movie. Multiple observations made over several months with NASA's Chandra X-ray Observatory and the Hubble Space Telescope captured the spectacle of matter and antimatter propelled to near the speed of light by the Crab pulsar, a rapidly rotating neutron star the size of Manhattan.

The photo offers an unprecedented, detailed view of the entire inner region of 30 Doradus, measuring 200 light-years wide by 150 light-years high. The nebula resides in the Large Magellanic Cloud (a satellite galaxy of the Milky Way), 170,000 light-years from Earth.

These two dazzling clusters of stars, called NGC 1850, are found in one of our neighboring galaxies, the Large Magellanic Cloud. The photo's centerpiece is a young, "globular-like" star cluster -- a type of object unknown in our own Milky Way Galaxy. The smaller second cluster is below and to the right of the main cluster. The stars are surrounded by a filigree pattern of diffuse gas [left], which scientists believe was created by the explosion of massive stars.

New pictures from the Hubble telescope are giving astronomers a detailed view of the Whirlpool galaxy's spiral arms and dust clouds, which are the birth sites of massive and luminous stars. This galaxy, also called M51 or NGC 5194, is having a close encounter with a nearby companion galaxy, NGC 5195, just off the upper edge of this image. The companion's gravitational influence is triggering star formation in the Whirlpool, as seen by the numerous clusters of bright, young stars [highlighted in red].

From ground-based telescopes, this cosmic object -- the glowing remains of a dying, Sun-like star -- resembles the head and thorax of a garden-variety ant. But this dramatic Hubble telescope image of the so-called "ant nebula" (Menzel 3, or Mz 3) shows even more detail, revealing the "ant's" body as a pair of fiery lobes protruding from the dying star

This ghostly apparition is actually an interstellar cloud caught in the process of destruction by strong radiation from a nearby hot star. This haunting picture, snapped by the Hubble telescope, shows a cloud illuminated by light from the bright star Merope. Located in the Pleiades star cluster, the cloud is called IC 349 or Barnard's Merope Nebula

Glowing like a multi-faceted jewel, the planetary nebula IC 418 lies about 2,000 light-years from Earth in the constellation Lepus. In this picture, the Hubble telescope reveals some remarkable textures weaving through the nebula. Their origin, however, is still uncertain.

In the year 1054 A.D., Chinese astronomers were startled by the appearance of a new star, so bright that it was visible in broad daylight for several weeks. Today, the Crab Nebula is visible at the site of that bright star. Located about 6,500 light-years from Earth, the Crab Nebula is the remnant of a star that began its life with about 10 times the mass of our Sun. Its life ended on July 4, 1054 when it exploded as a supernova. In this image, the Hubble telescope has zoomed in on the center of the Crab to reveal its structure with unprecedented detail

A huge, billowing pair of gas and dust clouds is captured in this stunning Hubble telescope picture of the super-massive star Eta Carinae.

Even though Eta Carinae is more than 8,000 light-years away, features 10 billion miles across (about the diameter of our solar system) can be distinguished. Eta Carinae suffered giant outburst about 150 years ago, when it became one of the brightest stars in the southern sky. Though the star released as much visible light as a supernova explosion, it survived the outburst. Somehow, the explosion produced two lobes and a large, thin equatorial disk, all moving outward at about 1.5 million miles per hour. Estimated to be 100 times heftier than our Sun, Eta Carinae may be one of the most massive stars in our galaxy

M2-9 is a striking example of a "butterfly" or a bipolar planetary nebula. Another more revealing name might be the "Twin Jet Nebula." If the nebula is sliced across the star, each side of it appears much like a pair of exhausts from jet engines. Indeed, because of the nebula's shape and the measured velocity of the gas, in excess of 200 miles per second, astronomers believe that the description as a super-super-sonic jet exhaust is quite apt. Ground-based studies have shown that the nebula's size increases with time, suggesting that the stellar outburst that formed the lobes occurred just 1,200 years ago.

The Hubble telescope is back at work, capturing this view of the butterfly-wing-shaped nebula, NGC 2346.

The nebula is about 2,000 light-years away from Earth in the direction of the constellation Monoceros. It represents the spectacular "last gasp" of a double-star system at the nebula's center.

Astronomers have caught a peek at a rare moment in the final stages of a star's life: a ballooning shroud of gas cast off by a dying star flicking on its stellar light bulb. The Hubble telescope has captured the unveiling of the Stingray nebula (Hen-1357), the youngest known planetary nebula.

Twenty years ago, the nebulous gas entombing the dying star wasn't hot enough to glow. The Stingray nebula (Hen-1357) is so named because its shape resembles a stingray fish. Images of a planetary nebula in its formative years can yield new insights into the last gasps of ordinary stars like our Sun.

Eerie, dramatic pictures from the Hubble telescope show newborn stars emerging from "eggs" — not the barnyard variety — but rather, dense, compact pockets of interstellar gas called evaporating gaseous globules (EGGs). Hubble found the "EGGs," appropriately enough, in the Eagle nebula, a nearby star-forming region 7,000 light-years from Earth in the constellation Serpens

This Hubble telescope image shows one of the most complex planetary nebulae ever seen, NGC 6543, nicknamed the "Cat's Eye Nebula." Hubble reveals surprisingly intricate structures including concentric gas shells, jets of high-speed gas, and unusual shock-induced knots of gas. Estimated to be 1,000 years old, the nebula is a visual "fossil record" of the dynamics and late evolution of a dying star.

The Helix Nebula is a glowing gas cloud around a dying Sun-like star. It is 650 light years away. This view combines photos from the Hubble Space Telescope and Kitt Peak National Observatory in Arizona.

November 2002 ~ The Little Ghost Nebula has a ghostly cloud of gas and dust surrounding the central dying star.

The Retina Nebula - Filamentary Type

January 2000 ~ The Eskimo Nebula is comprised of a ring of comet-shaped objects facing away from the dying central star. This nebula began forming about 10,000 years ago, and is about 5000 light years away from Earth. In this photograph, red represents nitrogen, green is hydrogen, blue is oxygen, and violet is helium.