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Artist's Concept of Galaxy Evolution Explorer
Credit: Artist's concept of Galaxy Evolution Explorer
The Galaxy Evolution Explorer was launched on April 28, 2003. Its mission is to study the shape, brightness, size and distance of galaxies across 10 billion years of cosmic history.
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Nature vs. Nurture in the Cosmos
Credit: NASA/JPL-Caltech/Las Campanas
A classic spiral galaxy with open arms and vigorous star formation, the young galaxy NGC 300 is located about seven million light-years away in the constellation Sculptor. Image is from NASA's Galaxy Evolution Explorer.
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Comet-like Tail Discovered Behind Speeding Star
Credit: NASA/JPL-Caltech.
A new ultraviolet mosaic from NASA's Galaxy Evolution Explorer shows a speeding star that is leaving an enormous trail of "seeds" for new solar systems. The star, named Mira (pronounced my-rah) after the latin word for "wonderful," is shedding material that will be recycled into new stars, planets and possibly even life as it hurls through our galaxy.
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NASA Telescope Makes Surprise Observations
The star GJ 3685A just happened to be in the Galaxy Evolution Explorer's field of view while the telescope was busy observing galaxies. This series of images shows the star flaring in UV light.
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Shockingly Large Explosion from Tiny Star System
Credit: NASA/JPL-Caltech
This image, from the far-ultraviolet detector on GALEX, was processed to enhance the appearance of the diffuse emissions from the shell around Z Cam.
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Discovery Suggests New Way Galaxies Might Form
Credit: NASA/JPL/DSS.
NASA's GALEX observatory spotted dwarf galaxies (in circles) growing inside the Leo Ring of interstellar gas, a region that is invisible to optical telescope but visible to GALEX's ultraviolet-scanning instruments.
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Dark Energy - Galaxy Evolution Explorer Findings
Credit: NASA/JPL-Caltech
New results from NASA's Galaxy Evolution Explorer and the Anglo-Australian Telescope atop Siding Spring Mountain in Australia confirm that dark energy (represented by purple grid) is a smooth, uniform force that now dominates over the effects of gravity (green grid). The observations follow from careful measurements of the separations between pairs of galaxies (examples of such pairs are illustrated here).
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Cosmic Grim Reaper Seen For First Time
Credit: Kevin Schawinski (Oxford), NASA/GALEX/HST, COSMOS.
The red supergiant underwent five stages in the life cycle of a star. The yellowish regions represent visible images taken with the Hubble Space Telescope, over which are the blue ultraviolet images taken with GALEX. Since GALEX doesn't have Hubble's spatial resolution, the blue blobs show up as blurry and larger than reality.
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Plowing Through the Depths of Space
Credit: NASA/JPL-Caltech
A runaway star, plowing through the depths of space and piling up interstellar material before it, can be seen in this ultraviolet image from NASA’s Galaxy Evolution Explorer. The star, called CW Leo, is hurtling through space at about 204,000 miles per hour (91 kilometers per second), or roughly 265 times the speed of sound on Earth.
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Helix Nebula
Credit: NASA/JPL-Caltech
This is the Helix nebula, as seen in ultraviolet light. It is a star like our sun but at the very end of its life. The star is a small dot in the center, surrounded by billowy layers of expelled material. This image was released May 5, 2005.
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The Galaxy Next Door
Credit: NASA/JPL-Caltech
Hot stars burn brightly in this new image from NASA's Galaxy Evolution Explorer, showing the ultraviolet side of a familiar face. At approximately 2.5 million light-years away, the Andromeda galaxy, or M31, is our Milky Way's largest galactic neighbor. The entire galaxy spans 260,000 light-years across—a distance so large, it took 11 different image segments stitched together to produce this view of the galaxy next door.
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Cosmic Cartwheel of Color
Credit: NASA/JPL-Caltech
This image of the Cartwheel galaxy shows a rainbow of multi-wavelength observations from NASA missions, including the Galaxy Evolution Explorer (blue), the Hubble Space Telescope (green), the Spitzer Space Telescope (red) and the Chandra X-ray Observatory (purple).
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Star Formation in the Suburbs
Credit: NASA/JPL-Caltech
A galaxy sprouts stars far from its central hub, as seen here where the blue dots line the red, spindly, spiral arms. Ultraviolet data from the Galaxy Evolution Explorer are color-coded blue and green, and radio observations from a ground-based telescope are red. This image was released April 16, 2008.
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It Takes Two to Tango
Credit: NASA/JPL-Caltech
Astronomers suspect that this pair of galaxies is locked in a gravitational dance. In this ultraviolet image, a spiral arm from the central galaxy appears to be wrapped around the smaller galaxy, located to its lower right. This image was released July 28, 2006.
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Dissecting a Galaxy
Credit: NASA/JPL-Caltech
Dissecting a Galaxy By combining ultraviolet data from the Galaxy Evolution Explorer with infrared observations from NASA's Spitzer Space Telescope, astronomers get a clear picture of the various components of a galaxy. In this image, the dust detected in infrared light is shown in red, while stars detected in ultraviolet light are blue. This image was released April 28, 2009.
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Ghostly Galaxy
Credit: NASA/JPL-Caltech
These images show the galaxy nicknamed "Ghost of Mirach" in visible-light (left) and in ultraviolet (right) as seen by the Galaxy Evolution Explorer. A ring around the galaxy -- which is the white spot in the center of both images -- seems to "materialize" in the ultraviolet view. This image was released Oct. 31, 2008.
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Watching Galaxies Grow Old
Credit: NASA/JPL-Caltech
Observations from the Galaxy Evolution Explorer allowed astronomers to trace the development of galaxies, from their wild, youthful days to their more settled, older years.
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Black Hole Swallows a Star
Credit: NASA/JPL-Caltech/JHU/STScI/Harvard-Smithsonian CfA
These images, taken with NASA's Galaxy Evolution Explorer and the Pan-STARRS1 telescope in Hawaii, show a brightening inside a galaxy caused by a flare from its nucleus. The arrow in each image points to the galaxy. The flare is a signature of the galaxy's central black hole shredding a star that wandered too close.
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The Beginning of the End of Star Formation
Credit: NASA/JPL-Caltech/SDSS/NRAO/ASIAA
Time is running out for the galaxy NGC 3801, seen in this composite image combining light from across the spectrum, ranging from ultraviolet to radio. NASA's Galaxy Evolution Explorer and other instruments have helped catch the galaxy NGC 3801 in the act of destroying its cold, gaseous fuel for new stars. Astronomers believe this marks the beginning of its transition from a vigorous spiral galaxy to a quiescent elliptical galaxy whose star-forming days are long past.
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How to Measure the Universe
Credit: NASA/JPL-Caltech
This diagram illustrates two ways to measure how fast the universe is expanding. In the past, distant supernovae, or exploded stars, have been used as "standard candles" to measure distances in the universe, and to determine that its expansion is actually speeding up. The supernovae glow with the same intrinsic brightness, so by measuring how bright they appear on the sky, astronomers can tell how far away they are. This is similar to a standard candle appearing fainter at greater distances (left-hand illustration).
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Little Galaxies Pack a Big Punch
Credit: NASA/JPL-Caltech
NASA's Galaxy Evolution Explorer is helping to solve a mystery — why do the littlest of galaxies produce the biggest of star explosions, or supernovae? These postage-stamp images were taken by the ultraviolet-sensing telescope — the top row shows four galaxies that each produced a typical supernova, while the bottom row shows four galaxies that each produced an ultra-bright supernova. All of the galaxies are located at the very center of the images. The top-row galaxies are roughly the size of our Milky Way galaxy.
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Planets Under a Red Sun
Credit: NASA/JPL-Caltech
This artist's concept illustrates a young, red dwarf star surrounded by three planets. Such stars are dimmer and smaller than yellow stars like our sun, which makes them ideal targets for astronomers wishing to take images of planets outside our solar system, called exoplanets.
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Ultraviolet Ring Around the Galaxies
Credit: NASA/ESA /JPL-Caltech/STScI /UCLA
Astronomers have found unexpected rings and arcs of ultraviolet light around a selection of galaxies, four of which are shown here as viewed by NASA's and the European Space Agency's Hubble Space Telescope. Observations from NASA's Galaxy Evolution Explorer (GALEX) picked out 30 elliptical and lens-shaped "early-type" galaxies with puzzlingly strong ultraviolet emissions but no signs of visible star formation.
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Now You See a Tail, Now You Don't
Credit: NASA/JPL-Caltech
NASA's Galaxy Evolution Explorer found a tail behind a galaxy called IC 3418. The star-studded tail can be seen on the left, as detected by the space telescope in ultraviolet light. The tail has escaped detection in visible light, as shown by the image on the right, taken by a visible-light telescope on the ground. This tail was created as the galaxy plunged into gas in a family of galaxies known as the Virgo cluster.
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Adding up Stars in a Galaxy
Credit: NASA/JPL-Caltech
This diagram illustrates the extent to which astronomers have been underestimating the proportion of small to big stars in certain galaxies. Data from NASA's Galaxy Evolution Explorer spacecraft and the Cerro Tololo Inter-American Observatory in Chile have shown that, in some cases, there can be as many as four times more small stars compared to large ones. This image was released Aug. 19, 2009.
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A Lesson in Counting Stars
Credit: NASA/JPL-Caltech/JHU
Galaxy Evolution Explorer spacecraft and the Cerro Tololo Inter-American Observatory in Chile. By combining the data, astronomers were able to learn that not all galaxies make stars of different sizes in the same quantities, as was previously assumed. In other words, the proportion of small to big stars can differ from galaxy to galaxy. This image was released Aug. 19, 2009.
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Galactic Neighbor M 33
Credit: NASA/JPL-Caltech
This image is a blend of the Galaxy Evolution Explorer's M33 image and another taken by NASA's Spitzer Space Telescope. M33, one of our closest galactic neighbors, is about 2.9 million light-years away in the constellation Triangulum, part of what's known as our Local Group of galaxies. This image was released April 28, 2009.
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Region Around Planetary Nebula NGC 3242
Credit: NASA/JPL-Caltech
This ultraviolet image from NASA's Galaxy Evolution Explorer shows NGC 3242, a planetary nebula frequently referred to as "Jupiter's Ghost." This image was released April 3, 2009.
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A Cosmic Embrace
Credit: NASA/JPL-Caltech
From 22 million light-years away, galaxy M106 extends two ultraviolet-bright spiral arms in this image from NASA's Galaxy Evolution Explorer. M106's extended arms are the blue filaments that curve around the edge of the galaxy, creating its outer disk. Tints of blue in the galaxy's arms reveal hot, young, massive stars. Meanwhile, traces of gold toward the center reveal an older stellar population and the presence of obscuring dust. This image was released April 28, 2008
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Odd Structure of NGC 1291
Credit: NASA/JPL-Caltech/CTIO
This image from NASA's Galaxy Evolution Explorer shows the galaxy NGC 1291, located about 33 million light-years away in the constellation Eridanus. NGC 1291 is notable for its unusual inner bar and outer ring structure. The Galaxy Evolution Explorer data was taken in December 2003.
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Big and Bright NGC 4569
Credit: NASA/JPL-Caltech/Palomar
This image from NASA's Galaxy Evolution Explorer shows the galaxy NGC 4569, located about four million light-years away in the constellation Virgo. It is one of the largest and brightest spiral galaxies found in the Virgo cluster of galaxies, the nearest major galaxy cluster to our Milky Way galaxy. The Galaxy Evolution Explorer data was taken in March 2004.
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Elliptical Galaxy NGC 1316
Credit: NASA/JPL-Caltech/CTIO
This image from NASA's Galaxy Evolution Explorer shows the galaxy NGC 1316, located about 62 million light-years away in the constellation Fornax. The elliptical-shaped galaxy may be in the late stages of merging with a smaller companion galaxy. The Galaxy Evolution Explorer data was taken in December 2003.
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A Real Shooting Star
Credit: NASA/JPL-Caltech
This artist's animation illustrates a star flying through our galaxy at supersonic speeds, leaving a 13-light-year-long trail of glowing material in its wake. The star, named Mira (pronounced my-rah) after the Latin word for "wonderful," sheds material that will be recycled into new stars, planets and possibly even life. NASA's Galaxy Evolution Explorer discovered the long trail of material behind Mira during its survey of the entire sky in ultraviolet light. This image was released Aug. 15, 2007.
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Supersonic Bullet
Credit: Courtesy of Andrew Davidhazy/Rochester Institute of Technology
A bullet traveling through air at about 1.5 times the speed of sound can be seen in this image. NASA's Galaxy Evolution Explorer captured an image of a racing star, called Mira, which resembles this bullet photo. The ultraviolet image shows a gigantic shock wave, called a bow shock, in front of the star, and an enormous, 13-light-year-long trail of turbulence in its wake. Nothing like this tail has ever been seen before. This image was created using an instrument called a shadowgraph. The image was released Aug. 15, 2007.
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Anatomy of a Shooting Star
Credit: NASA/JPL-Caltech
A close-up view of a star racing through space faster than a speeding bullet can be seen in this image from NASA's Galaxy Evolution Explorer. The star, called Mira (pronounced My-rah), is traveling at 130 kilometers per second, or 291,000 miles per hour. As it hurls along, it sheds material that will be recycled into new stars, planets and possibly even life. This image was released Aug. 15, 2007.
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Magnificent M81
Credit: NASA/JPL-Caltech
In a new ultraviolet image, the magnificent M81 spiral galaxy is shown at the center. The orbiting observatory spies the galaxy's "sizzling young starlets" as wisps of bluish-white swirling around a central golden glow. The tints of gold at M81's center come from a "senior citizen" population of smoldering stars. This image was released May 1, 2007.
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Scene of Multiple Explosions
Credit: NASA/JPL-Caltech
This composite image shows Z Camelopardalis, or Z Cam, a double-star system featuring a collapsed, dead star, called a white dwarf, and a companion star, as well as a ghostly shell around the system. The massive shell provides evidence of lingering material ejected during and swept up by a powerful classical nova explosion that occurred probably a few thousand years ago. This image was released March 7, 2007.
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Explosions — Large and Small
Credit: NASA/JPL-Caltech
This animation shows an artist's concept of Z Camelopardalis (Z Cam), a stellar system featuring a collapsed, dead star, or white dwarf, and a companion star. The white dwarf, the bright white object within the disk on the left, sucks matter from its more sedate companion star, on the right. The stolen material forms a rotating disk of gas and dust around the white dwarf. This image was released March 7, 2007.
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Older Galaxy Pair Has Surprisingly Youthful Glow
Credit: NASA/JPL-Caltech/ETSU
A pair of interacting galaxies might be experiencing the galactic equivalent of a mid-life crisis. For some reason, the pair, called Arp 82, didn't make their stars early on as is typical of most galaxies. Instead, they got a second wind later in life — about 2 billion years ago — and started pumping out waves of new stars as if they were young again. This image was released Jan. 10, 2007.
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Black Hole Grabs Starry Snack
Credit: NASA/JPL-Caltech
This artist's concept shows a supermassive black hole at the center of a remote galaxy digesting the remnants of a star. NASA's Galaxy Evolution Explorer had a "ringside" seat for this feeding frenzy, using its ultraviolet eyes to study the process from beginning to end. This image was released Dec. 4, 2006.
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Baby Galaxies in the Adult Universe
Credit: NASA/JPL-Caltech
This artist's conception illustrates the decline in our universe's "birth-rate" over time. When the universe was young, massive galaxies were forming regularly, like baby bees in a bustling hive. In time, the universe bore fewer and fewer "offspring," and newborn galaxies (white circles) matured into older ones more like our own Milky Way (spirals).
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Fires of Galactic Youth
Credit: NASA/JPL-Caltech
This animation shows a typical young galaxy, teeming with hot, newborn stars and exploding supernovas. The supernovas are seen as white flashes of light. This image was released Dec. 21, 2004.
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Nearby Newborns
Credit: NASA/JPL-Caltech/Johns Hopkins
This image shows six of the three-dozen "ultraviolet luminous galaxies" spotted in our corner of the universe by NASA's Galaxy Evolution Explorer. These massive galaxies greatly resemble newborn galaxies that were common in the early universe. The discovery came as a surprise, because astronomers had thought that the universe's "birth-rate" had declined, and that massive galaxies were no longer forming. This image was released Dec. 21, 2004.
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The Lives and Times of Stars
Credit: NASA/JPL-Caltech/Johns Hopkins
This image of the nearby spiral galaxy M101, better known as the Pinwheel Galaxy, is a three-color combination of images from NASA's Galaxy Evolution Explorer (GALEX) spacecraft. The ultraviolet light, seen in blue in the arms of the galaxy, shows young stars (only 10 million years old), while the diffuse green visible light traces stars that have been living for more than 100 years. The red visible light image shows the stars that formed over a billion years ago.


























































































