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Galaxy Triplet ARP 274
On April 1-2, the Hubble Spa
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4/6/09
| Description |
On April 1-2, the Hubble Space Telescope photographed the winning target in the Space Telescope Science Institute's 'You Decide' competition in celebration of the International Year of Astronomy (IYA). The winner is a group of galaxies called Arp 274. The striking object received 67,021 votes out of the nearly 140,000 votes cast for the six candidate targets. Arp 274, also known as NGC 5679, is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (to the far left) is more compact, but shows evidence of star formation. Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left. The largest component is located in the middle of the three. It appears as a spiral galaxy, which may be barred. The entire system resides at about 400 million light-years away from Earth in the constellation Virgo. Hubble's Wide Field Planetary Camera 2 was used to image Arp 274. Blue, visible and infrared filters were combined with a filter that isolates hydrogen emission. The colors in this image reflect the intrinsic color of the different stellar populations that make up the galaxies. Yellowish older stars can be seen in the central bulge of each galaxy. A bright central cluster of stars pinpoint each nucleus. Younger blue stars trace the spiral arms, along with pinkish nebulae that are illuminated by new star formation. Interstellar dust is silhouetted against the starry population. A pair of foreground stars inside our own Milky Way are at far right. The International Year of Astronomy is the celebration of the 400th anniversary of Galileo's first observations with a telescope. People around the world came together to participate in the IYA's 100 Hours of Astronomy, April 2 to 5. This global astronomy event was geared toward encouraging as many people as possible to experience the night sky. Image Credit: NASA, ESA, and M. Livio and the Hubble Heritage Team (STScI/AURA) |
| Date |
4/6/09 |
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Pretty as a Picture
The Hubble community bids fa
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5/11/09
| Description |
The Hubble community bids farewell to the soon-to-be decommissioned Wide Field Planetary Camera 2 (WFPC2) onboard the Hubble Space Telescope. In tribute... |
| Date |
5/11/09 |
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Pretty as a Picture
The Hubble community bids fa
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5/11/09
| Description |
The Hubble community bids farewell to the soon-to-be decommissioned Wide Field Planetary Camera 2 (WFPC2) onboard the Hubble Space Telescope. In tribute to Hubble's longest-running optical camera, a planetary nebula has been imaged as WFPC2's final "pretty picture." This planetary nebula is known as Kohoutek 4-55 (or K 4-55). It is one of a series of planetary nebulae that were named after their discoverer, Czech astronomer Lubos Kohoutek. A planetary nebula contains the outer layers of a red giant star that were expelled into interstellar space when the star was in the late stages of its life. Ultraviolet radiation emitted from the remaining hot core of the star ionizes the ejected gas shells, causing them to glow. In the case of K 4-55, a bright inner ring is surrounded by a bipolar structure. The entire system is then surrounded by a faint red halo, seen in the emission by nitrogen gas. This multi-shell structure is fairly uncommon in planetary nebulae. This Hubble image was taken by WFPC2 on May 4, 2009. The colors represent the makeup of the various emission clouds in the nebula: red represents nitrogen, green represents hydrogen, and blue represents oxygen. K 4-55 is nearly 4,600 light-years away in the constellation Cygnus. The WFPC2 instrument, which was installed in 1993 to replace the original Wide Field/Planetary Camera, will be removed to make room for Wide Field Camera 3 during the STS-125 mission. During the camera's amazing, nearly 16-year run, WFPC2 provided outstanding science and spectacular images of the cosmos. Some of its best-remembered images are of the Eagle Nebula pillars, Comet P/Shoemaker-Levy 9's impacts on Jupiter's atmosphere, and the 1995 Hubble Deep Field -- the longest and deepest Hubble optical image of its time. Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA) and R. Sahai and J. Trauger (Jet Propulsion Laboratory) |
| Date |
5/11/09 |
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Hubble Image of He2-90
This mysterious object that
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8/31/00
| Date |
8/31/00 |
| Description |
This mysterious object that seems to defy classification was found by astronomers using NASA's Hubble Space Telescope. The object has been classified as a planetary nebula, the glowing remains of a Sun-like star in its death throes, although the Hubble observations suggest it may not fit that classification, either. A quick glance at the Hubble picture at top shows that the object, He2-90, looks like a young, dust-enshrouded star with narrow jets of material resembling strings of beads streaming from each side. The other light streaks running diagonally from He2-90 are artificial effects of the telescope's optical system. Each jet possesses at least six bright clumps of gas speeding along at rates estimated to be at least 600,000 kilometers an hour (375,000 miles an hour). These gaseous clumps are ejected into space about every 100 years and may be caused by periodic instabilities in He2-90's accretion disk. Jets from very young stars behave in a similar way. Deep images taken from a terrestrial observatory show each jet extending at least 100,000 astronomical units (one astronomical unit equals the Earth-Sun distance, 150 million kilometers or 93 million miles). The Hubble astronomers, Dr. Raghvendra Sahai of NASA's Jet Propulsion Laboratory, Pasadena, Calif., and Lars-Ake Nyman of the European Southern Observatory, Chile, and Onsala Space Observatory, Sweden, suspect that He2-9 is a pair of aging stars masquerading as a single youngster. One member of the duo is a bloated red giant star shedding matter from its outer layers. This matter is then captured by gravity in a rotating accretion disk around a compact partner, most likely a young white dwarf (the collapsed remnant of a Sun-like star). The stars are not visible in the Hubble images because they're obscured by a disk of dust. The jets' relatively modest speed implies that one member of the duo is a white dwarf. An accretion disk needs gravity to form. For gravity to create He2-90's disk, the two stars must reside at a cozy distance from each other: within about 10 astronomical units. Astronomers are uncertain about the details, but they believe that magnetic fields associated with accretion disks produce and constrict the pencil-thin jets seen in the Hubble image. The close-up Hubble photo at bottom shows a dark, flaring, disk-like structure (off-center) bisecting the bright light from the object. The disk is seen edge-on. Although this disk is too large to be an accretion disk, it may provide indirect proof of the disk's existence. Most theories for producing jets require the presence of an accretion disk. The round, white objects at the lower left and upper right corners are two bright clumps of gas in the jets, which are close to the companion star. The astronomers traced the jets to within 1,000 astronomical units of the central obscured star. The star ejected this material about 30 years ago. This oddball star was discovered during an imaging survey of planetary nebulae. The images were taken Sept. 28, 1999 with Hubble's Wide Field and Planetary Camera 2. The images and results appear in the Aug. 1 issue of the Astrophysical Journal Letters. JPL designed and built the Wide Field and Planetary Camera 2. The Space Telescope Science Institute, Baltimore, Md, manages space operations for the Hubble Space Telescope for NASA's Office of Space Science, Washington, D.C. The Institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract with NASA's Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. ##### |
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WFPC2--Horsehead Nebula
In honor of the 11th birthda
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4/24/01
| Date |
4/24/01 |
| Description |
In honor of the 11th birthday of NASA's Hubble Space Telescope, and by popular demand, the Hubble team has released this new image of the Horsehead nebula, taken by its Wide Field and Planetary Camera 2 (WFPC2), designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Last year, 5,000 online voters, including students, teachers, and professional and amateur astronomers, chose the nebula as an astronomical target for Hubble to observe. Rising from a sea of dust and gas like a giant seahorse, the Horsehead nebula is one of the most photographed objects in the sky. Hubble's WFPC2 camera took a close-up look at this heavenly icon, revealing the cloud's intricate structure. The Horsehead, also known as Barnard 33, is a cold, dark cloud of gas and dust silhouetted against the bright red nebula IC 434. The bright area at the top left edge is a young star still embedded in its nursery of gas and dust. But radiation from this hot star is eroding the stellar nursery. The top of the nebula also is being sculpted by radiation from a massive star located out of Hubble's field-of-view. The nebula was first discovered on a photographic plate in the late 1800s. It is located in the constellation Orion just south of the bright star Zeta Orionis, which is easily visible to the unaided eye as the left-hand star in the line of three that form Orion's Belt. This image was composed by the Hubble Heritage Team at the Space Telescope Science Institute, Baltimore, Md. The team superimposed Hubble data onto ground-based data taken by Nigel A. Sharp at the .9-meter (35-inch) telescope at the National Science Foundation's Kitt Peak National Observatory near Tucson, Ariz. Additional images and an animation of the Horsehead nebula are available at http://heritage.stsci.edu/public/2001may/supplemental.html . NASA's Hubble Space Telescope was launched on April 24, 1990. The Hubble is a project of international cooperation between NASA and the European Space Agency (ESA). JPL, which designed and built the WFPC2 camera, is a division of the California Institute of Technology in Pasadena. Additional information about the Hubble Space Telescope and more images are available at http://www.stsci.edu . More information about WFPC2 is at http://wfpc2.jpl.nasa.gov . Image Credit: NASA, NOAO, ESA and The Hubble Heritage Team (STScI/AURA) Acknowledgment: K. Noll (Hubble Heritage PI/STScI), C. Luginbuhl (USNO), F. Hamilton (Hubble Heritage/STScI) ##### |
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SEASONAL CHANGES IN MARS' NO
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These images, which seem to
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| Description |
These images, which seem to have been taken while NASA's Hubble Space Telescope (HST) was looking directly down on the Martian North Pole, were actually created by assembling mosaics of three sets of images taken by HST in October, 1996 and in January and March, 1997 and projecting them to appear as they would if seen from above the pole. This first mosaic is a view which could not actually be seen in nature because at this season a portion of the pole would have actually been in shadow, the last view, taken near the summer solstice, would correspond to the Midnight Sun on Earth with the pole fully illuminated all day. The resulting polar maps begin at 50 degrees N latitude and are oriented with 0 degrees longitude at the 12 o'clock position. This series of pictures captures the seasonal retreat of Mars' north polar cap. October 1996 (early spring in the Northern hemisphere): In this map, assembled from images obtained between Oct. 8 and 15, the cap extends down to 60 degrees N latitude, nearly it's maximum winter extent. (The notches are areas where Hubble data were not available). A thin, comma-shaped cloud of dust can be seen as a salmon-colored crescent at the 7 o'clock position. The cap is actually fairly circular about the geographic pole at this season, the bluish "knobs" where the cap seems to extend further are actually clouds that occurred near the edges of the three separate sets of images used to make the mosaic. January 1997 (mid-spring): Increased warming as spring progresses in the northern hemisphere has sublimated the carbon dioxide ice and frost below 70 degrees north latitude. The faint darker circle inside the cap boundary marks the location of circumpolar sand dunes (see March '97 map), these dark dunes are warmed more by solar heating than are the brighter surroundings, so the surface frost sublimates from the dunes earlier than from the neighboring areas. Particularly evident is the marked hexagonal shape of the polar cap at this season, noted previously by HST in 1995 and Mariner 9 in 1972, this may be due to topography, which isn't well known, or to wave structure in the circulation. This map was assembled from WFPC2 images obtained between Dec. 30, 1996 and Jan. 4, 1997. March 30, 1997 (early summer): The cap has fully retreated to its remnant core of water-ice. This residual cap is actually almost cut into two by a large, horn-shaped canyon called Chasma Borealis which is cut deeply into the polar terrain. The HST images also reveal a curious layered terrain which is evidence of past climatic changes on Mars. The sublimation of all of the carbon dioxide has exposed the ring of dark sand dunes which encircle the North Polar Cap. Outliers of ice persist south of the polar sand sea (between the 3 o'clock and 9 o'clock positions). The bright circular features at 3, 6, and 9 o'clock are ice-filled craters. All images were taken with the Wide Field and Planetary Camera 2. The color is constructed from images taken in red (673 nm) , blue (410 nm) and green (502 nm) light. The resolution at the North Pole ranges from about 115 km/pixel in October '96 to about 45 km/pixel in March '97. Credit: Phil James (Univ. Toledo), Todd Clancy (Space Science Inst., Boulder, CO), Steve Lee (Univ. Colorado), and NASA |
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Hubble Follows the Rotation
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| title |
Hubble Follows the Rotation of the Asteroid Vesta |
| description |
This is a NASA Hubble Space Telescope series of 24 images showing the full 5.34-hour rotation of the 325-mile diameter (525 kilometer) asteroid Vesta. Hubble resolves features as small as 50 miles across, allowing astronomers to map Vesta's geologically diverse terrain. The surface is a complex record of Vesta's four billion-year history. Features include ancient lava flows, and a gigantic impact basin that is so deep, it exposes the asteroid's subsurface, or mantle. This sequence was taken with Hubble's Wide Field Planetary Camera 2 between November 28 and December 1, 1994, when Vesta was at a distance of 156 million miles from Earth. When combined with ground-based data, astronomers will be able to make the first geochemical map of Vesta's surface. *Image Credit*: B. Zellner (Georgia Southern University) and NASA |
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Hubble Captures Full View of
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| title |
Hubble Captures Full View of Uranus's Rings on Edge |
| date |
08.14.2007 |
| description |
NASA's Hubble Space Telescope captures a rare view of the entire ring system of the planet Uranus, tilted edge-on to Earth. The rings were photographed with Hubble's Wide Field Planetary Camera 2 on August 14, 2007. The edge-on rings appear as spikes above and below the planet. The rings cannot be seen running fully across the face of the planet because the bright glare of the planet has been blocked out in the HST photo (a small amount of residual glare appears as a fan-shaped image artifact, along with an edge between the exposure for the inner and outer rings). A much shorter color exposure of the planet has been photo-composited to show its size and position relative to the ring plane. Earthbound astronomers only see the rings' edge every 42 years as the planet follows a leisurely 84-year orbit about the Sun. However, the last time the rings were tilted edge-on to Earth astronomers didn't even know they existed. The fainter outer rings appear in the 2003 Hubble Space Telescope images, but were not noticed there until they were seen in the 2005 images and the previous ones were analyzed more carefully. Uranus has a total of 13 dusty rings. Credit: NASA [ http://www.nasa.gov/ ], ESA [ http://www.spacetelescope.org/ ], and M. Showalter (SETI Institute) |
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Comet P/Shoemaker-Levy 9 Fra
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| title |
Comet P/Shoemaker-Levy 9 Fragments |
| date |
05.17.1994 |
| description |
Last panoramic mosaic of comet P/Shoemaker-Levy 9 (SL-9) taken by the Hubble Space Telescope. The comet had broken into 21 fragments, all of which impacted Jupiter in mid-July of 1994. This image was taken on 17 May 1994 through the red filter of the Wide-Field Planetary Camera 2. At this time, the comet was about 660 million km from Earth. The comet fragments stretch across 1.1 million km of space. (HST, STScI-PR94-26d) *Image Credit*: NASA |
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Hubble Captures Detailed Ima
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| title |
Hubble Captures Detailed Image of Uranus' Atmosphere |
| date |
07.03.1995 |
| description |
Hubble Space Telescope has peered deep into Uranus' atmosphere to see clear and hazy layers created by a mixture of gases. Using infrared filters, Hubble captured detailed features of three layers of Uranus' atmosphere. Hubble's images are different from the ones taken by the Voyager 2 spacecraft, which flew by Uranus 10 years ago. Those images - not taken in infrared light - showed a greenish-blue disk with very little detail. The infrared image allows astronomers to probe the structure of Uranus' atmosphere, which consists of mostly hydrogen with traces of methane. The red around the planet's edge represents a very thin haze at a high altitude. The haze is so thin that it can only be seen by looking at the edges of the disk, and is similar to looking at the edge of a soap bubble. The yellow near the bottom of Uranus is another hazy layer. The deepest layer, the blue near the top of Uranus, shows a clearer atmosphere. Image processing has been used to brighten the rings around Uranus so that astronomers can study their structure. In reality, the rings are as dark as black lava or charcoal. This false color picture was assembled from several exposures taken July 3, 1995 by the Wide Field Planetary Camera-2. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu *Image Credit*: Erich Karkoschka (University of Arizona Lunar & Planetary Lab) and NASA |
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Hubble Spots Northern Hemisp
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| title |
Hubble Spots Northern Hemispheric Clouds on Uranus |
| date |
07.31.1997 |
| description |
Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time. Uranus is sometimes called the "sideways" planet, because its rotation axis tipped more than 90 degrees from the planet's orbit around the Sun. The "year" on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness). Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds. Two images are shown here. The "aqua" image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb (rightmost edge). The "red" image (on the right) is taken at 6,190 Angstroms, and is sensitive to absorption by methane molecules in the planet's atmosphere. The banded structure of Uranus is evident, and the small cloud near the northern limb is now visible. Scientists are expecting that the discrete clouds and banded structure may become even more pronounced as Uranus continues in its slow pace around the Sun. "Some parts of Uranus haven't seen the Sun in decades," says Dr. Hammel, "and historical records suggest that we may see the development of more banded structure and patchy clouds as the planet's year progresses." Some scientists have speculated that the winds of Uranus are not symmetric around the planet's equator, but no clouds were visible to test those theories. The new data will provide the opportunity to measure the northern winds. Hammel and colleagues expect to have results soon. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by, the Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu *Image Credit*: Heidi Hammel (Massachusetts Institute of Technology), NASA |
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Neptune's Stormy Disposition
| title |
Neptune's Stormy Disposition |
| date |
08.11.1998 |
| description |
Using powerful ground-and space-based telescopes, scientists have obtained a moving look at some of the wildest, weirdest weather in the solar system. Combining simultaneous observations of Neptune made with the Hubble Space Telescope and NASA's Infrared Telescope Facility on Mauna Kea, Hawaii, a team of scientists led by Lawrence A. Sromovsky of the University of Wisconsin-Madison has captured the most insightful images to date of a planet whose blustery weather -- monster storms and equatorial winds of 900 miles per hour -- bewilders scientists. The weather on Neptune, the eighth planet from the sun, is an enigma to begin with. The mechanism that drives its near-supersonic winds and giant storms has yet to be determined. On Earth, weather is driven by energy from the sun as it heats the atmosphere and oceans. On Neptune, the sun is 900 times dimmer and scientists have yet to understand how Neptune's weather-generating machinery can be so efficient. "It's an efficient weather machine compared to Earth," said Sromovsky. "It seems to run on almost no energy." In an effort to dissect the distant planet's atmosphere and monitor its bizarre weather, Sromovsky and his colleagues obtained a series of measurements and images over the span of three of Neptune's rotations. From those observations, Sromovsky said it is possible to measure Neptune's circulation and view a "strange menagerie of variable, discrete cloud features and zonal bands" of weather. Moreover, the new observations enabled Sromovsky's team to probe some of the deeper features of the atmosphere and to map Neptune's cloud tops. "We can show some clouds are higher than others, that altitudes vary," he said. Knowing something about the topography of Neptune's clouds, provides a direct way to measure Neptune's powerful winds. A looming mystery, he said, is the fate of huge dark spots, possibly giant storms. When the planetary probe Voyager visited Neptune in 1989, it detected the Great Dark Spot, a pulsating feature nearly the size of the Earth itself. Two years ago, Hubble observations showed the spot had disappeared, and that another, smaller spot had emerged. But instead of growing to a large-scale storm like the Great Dark Spot, the new spot appears to be trapped at a fixed latitude and may be declining in intensity, said Sromovsky, a senior scientist at UW-Madison's Space Science and Engineering Center. "They behave like storms, and the Great Dark Spot was an exaggerated features we haven't seen on any other planet. They seem to come and go, and rather than an exciting development of these dark spots, they dissipate." Another strange aspect of the distant planet's weather are distinct bands of weather that run parallel to the Neptunian equator. The weather bands encircle the planet and, in some respects, may be similar to the equatorial region of the Earth where tropical heat provides abundant energy to make clouds. "We can see regions of latitude where Neptune, consistently generates bright clouds," said Sromovsky. The regions are both above and below the planet's equator, but he added that it was uncertain what their explanation is in terms of atmospheric circulation. Sromovsky said that compared to the look provided by the Voyager spacecraft, Neptune is a different place: "The character of Neptune is different from what it was at the time of Voyager. The planet seems stable, yet different." Sromovsky's Hubble observations were made with Wide Field Planetary Camera 2 and the Near Infrared Camera and Multi-Object Spectrometer. The different instruments allowed observations to be made in a variety of wavelengths, each providing a different set of information about Neptune's clouds, their structures and how they circulate. *Image Credit*: NASA |
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Hubble Tracks Clouds on Uran
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| title |
Hubble Tracks Clouds on Uranus |
| date |
07.28.1997 |
| description |
Taking its first peek at Uranus, NASA Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has detected six distinct clouds in images taken July 28,1997. The image on the right, taken 90 minutes after the left-hand image, shows the planet's rotation. Each image is a composite of three near-infrared images. They are called false-color images because the human eye cannot detect infrared light. Therefore, colors corresponding to visible light were assigned to the images. (The wavelengths for the "blue,""green," and "red" exposures are 1.1, 1.6, and 1.9 micrometers, respectively.) At visible and near-infrared light, sunlight is reflected from hazes and clouds in the atmosphere of Uranus. However, at near-infrared light, absorption by gases in the Uranian atmosphere limits the view to different altitudes, causing intense contrasts and colors. In these images, the blue exposure probes the deepest atmospheric levels. A blue color indicates clear atmospheric conditions, prevalent at mid-latitudes near the center of the disk. The green exposure is sensitive to absorption by methane gas, indicating a clear atmosphere, but in hazy atmospheric regions, the green color is seen because sunlight is reflected back before it is absorbed. The green color around the south pole (marked by "+") shows a strong local haze. The red exposure reveals absorption by hydrogen, the most abundant gas in the atmosphere of Uranus. Most sunlight shows patches of haze high in the atmosphere. A red color near the limb (edge) of the disk indicates the presence of a high-altitude haze. The purple color to the right of the equator also suggests haze high in the atmosphere with a clear atmosphere below. The five clouds visible near the right limb rotated counterclockwise during the time between both images. They reach high into the atmosphere, as indicated by their red color. Features of such high contrast have never been seen before on Uranus. The clouds are almost as large as continents on Earth, such as Europe. Another cloud (which barely can be seen) rotated along the path shown by the black arrow. It is located at lower altitudes, as indicated by its green color. The rings of Uranus are extremely faint in visible light but quite prominent in the near infrared. The brightest ring, the epsilon ring, has a variable width around its circumference. Its widest and thus brightest part is at the top in this image. Two fainter, inner rings are visible next to the epsilon ring. Eight of the 10 small Uranian satellites, discovered by Voyager 2, can be seen in both images. Their sizes range from about 25 miles (40 kilometers) for Bianca to 100 miles (150 kilometers) for Puck. The smallest of these satellites have not been detected since the departure of Voyager 2 from Uranus in 1986. These eight satellites revolve around Uranus in less than a day. The inner ones are faster than the outer ones. Their motion in the 90 minutes between both images is, marked in the right panel. The area outside the rings was slightly enhanced in brightness to improve the visibility of these faint satellites. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/ *Image Credit*: NASA |
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More Images of NGC 6240
| Name |
More Images of NGC 6240 |
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HST Optical Image of GB1508+
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| Name |
HST Optical Image of GB1508+5714 |
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Hubble Optical Image of Jupi
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| Name |
Hubble Optical Image of Jupiter |
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Circinus Galaxy-Optical
| Name |
Circinus Galaxy-Optical |
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Hubble Optical Image of NGC
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| Name |
Hubble Optical Image of NGC 5315 |
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Hubble Space Telescope Image
…
| Name |
Hubble Space Telescope Image of central region of M15 |
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), Hubble Optical Image of N
…
| Name |
), Hubble Optical Image of NGC 1637, Close-Up, Merged Chandra X-ray Image of NGC 1637, Full Field, NOAO Optical Image of NGC 1637, X-ray/Optical Overlay of NGC 1637 |
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HST Optical Image of N63A
| Name |
HST Optical Image of N63A |
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Hubble Optical Image of Crab
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| Name |
Hubble Optical Image of Crab Nebula |
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X-ray/Optical Composite of C
…
| Name |
X-ray/Optical Composite of C153 (alternative color scheme) |
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HST Optical Image of C153
| Name |
HST Optical Image of C153 |
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Zoom into Spiral Galaxy C153
| Name |
Zoom into Spiral Galaxy C153 |
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A Grazing Encounter Between
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| Title |
A Grazing Encounter Between Two Spiral Galaxies |
| Full Description |
The larger and more massive galaxy is cataloged as NGC 2207 (on the left in the Hubble Heritage image), and the smaller one on the right is IC 2163. Strong tidal forces from NGC 2207 have distorted the shape of IC 2163, flinging out stars and gas into long streamers stretching out a hundred thousand light-years toward the right-hand edge of the image. Computer simulations, carried out by a team led by Bruce and Debra Elmegreen, demonstrate the leisurely timescale over which galactic collisions occur. In addition to the Hubble images, measurements made with the National Science Foundation's Very Large Array Radio Telescope in New Mexico reveal the motions of the galaxies and aid the reconstruction of the collision. The calculations indicate that IC 2163 is swinging past NGC 2207 in a counterclockwise direction, having made its closest approach 40 million years ago. However, IC 2163 does not have sufficient energy to escape from the gravitational pull of NGC 2207, and is destined to be pulled back and swing past the larger galaxy again in the future. The high resolution of the Hubble telescope image reveals dust lanes in the spiral arms of NGC 2207, clearly silhouetted against IC 2163, which is in the background. Hubble also reveals a series of parallel dust filaments extending like fine brush strokes along the tidally stretched material on the right-hand side. The large concentrations of gas and dust in both galaxies may well erupt into regions of active star formation in the near future. Trapped in their mutual orbit around each other, these two galaxies will continue to distort and disrupt each other. Eventually, billions of years from now, they will merge into a single, more massive galaxy. It is believed that many present-day galaxies, including the Milky Way, were assembled from a similar process of coalescence of smaller galaxies occurring over billions of years. This image was created from 3 separate pointings of Hubble. The Wide Field Planetary Camera 2 data sets were obtained by Debra Meloy Elmegreen (Vassar College), Bruce G. Elmegreen (IBM Research Division), Michele Kaufman (Ohio State U.), Elias Brinks (Universidad de Guanajuato, Mexico), Curt Struck (Iowa State University), Magnus Thomasson (Onsala Space Obs., Sweden), Maria Sundin (Goteborg University, Sweden), and Mario Klaric (Columbia, South Carolina). |
| Date |
11/04/1999 |
| NASA Center |
Hubble Space Telescope Center |
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Magnificant Details in a Dus
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| Title |
Magnificant Details in a Dusty Spiral Galaxy |
| Full Description |
In 1995, the majestic spiral galaxy NGC 4414 was imaged by the Hubble Space Telescope as part of the HST Key Project on the Extragalactic Distance Scale. An international team of astronomers, led by Dr. Wendy Freedman of the Observatories of the Carnegie Institution of Washington, observed this galaxy on 13 different occasions over the course of two months. Images were obtained with Hubble's Wide Field Planetary Camera 2 (WFPC2) through three different color filters. Based on their discovery and careful brightness measurements of variable stars in NGC 4414, the Key Project astronomers were able to make an accurate determination of the distance to the galaxy. The resulting distance to NGC 4414, 19.1 megaparsecs or about 60 million light-years, along with similarly determined distances to other nearby galaxies, contributes to astronomers' overall knowledge of the rate of expansion of the universe. In 1999, the Hubble Heritage Team revisited NGC 4414 and completed its portrait by observing the other half with the same filters as were used in 1995. The end result is a stunning full-color look at the entire dusty spiral galaxy. The new Hubble picture shows that the central regions of this galaxy, as is typical of most spirals, contain primarily older, yellow and red stars. The outer spiral arms are considerably bluer due to ongoing formation of young, blue stars, the brightest of which can be seen individually at the high resolution provided by the Hubble camera. The arms are also very rich in clouds of interstellar dust, seen as dark patches and streaks silhouetted against the starlight. |
| Date |
06/03/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
Mars and Acidalia
| Title |
Mars and Acidalia |
| Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained four images, which, together, show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered near the location of the Pathfinder landing site. Dark sand dunes that surround the polar cap merge into a large, dark region called Acidalia. This area, as shown by images from the Hubble telescope and other spacecraft, is composed of dark, sand-sized grains of pulverized volcanic rock. Below and to the left of Acidalia are the massive Martian canyon systems of Valles Marineris, some of which form long linear markings that were once thought by some to be canals. Early morning clouds can be seen along the left limb of the planet, and a large cyclonic storm composed of water ice is churning near the polar cap. |
| Date |
06/30/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
Mars and Elysium
| Title |
Mars and Elysium |
| Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained these four images, which, together, show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered near another volcanic region known as Elysium. This area shows many small, dark markings that have been observed by the Hubble telescope and other spacecraft to change as a result of the movement of sand and dust across the Martian surface. In the upper left of this image, at high northern latitudes, a large chevron-shaped area of water ice clouds mark a storm front. Along the right limb, a large cloud system has formed around the Olympus Mons volcano. |
| Date |
06/30/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
Mars and Syrtis Major
| Title |
Mars and Syrtis Major |
| Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained four images, which, together, show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. The dark feature known as Syrtis Major was first seen telescopically by the astronomer Christiaan Huygens in the 17th century. Many small, dark, circular impact craters can be seen in this region, attesting to the Hubble telescope's ability to reveal fine detail on the planet's surface. To the south of Syrtis is a large circular feature called Hellas. Viking and more recently Mars Global Surveyor have revealed that Hellas is a large and deep impact crater. These Hubble telescope pictures show it to be filled with surface frost and water ice clouds. Along the right limb, late afternoon clouds have formed around the volcano Elysium. |
| Date |
06/30/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
Mars and Tharsis
| Title |
Mars and Tharsis |
| Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained four images, which together show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered on the region of the planet known as Tharsis, home of the largest volcanoes in the solar system. The bright, ring- like feature just to the left of center is the volcano Olympus Mons, which is more than 340 miles (550 kilometers) across and 17 miles (27 kilometers) high. Thick deposits of fine-grained, windblown dust cover most of this hemisphere. The colors indicate that the dust is heavily oxidized ("rusted"), and millions (or perhaps billions) of years of dust storms have homogenized its composition. Prominent late afternoon clouds along the right limb of the planet can be seen. |
| Date |
06/30/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
An Expanding Bubble in Space
| Title |
An Expanding Bubble in Space |
| Full Description |
Astronomers, using the Wide Field Planetary Camera 2 on board NASA's Hubble Space Telescope in October and November 1997 and April 1999, imaged the Bubble Nebula (NGC 7635) with unprecedented clarity. For the first time, they are able to understand the geometry and dynamics of this very complicated system. Earlier pictures taken of the nebula with the Wide Field Planetary Camera 1 left many issues unanswered, as the data could not be fully calibrated for scientific use. In addition, those data never imaged the enigmatic inner structure presented here. The remarkably spherical "Bubble" marks the boundary between an intense wind of particles from the star and the more quiescent interior of the nebula. Research Team: Donald Walter (South Carolina State University), Paul Scowen, Jeff Hester, Brian Moore (Arizona State University), Reggie Dufour, Patrick Hartigan and Brent Buckalew (Rice University). |
| Date |
01/13/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
N81 in the Small Magellanic
…
| Title |
N81 in the Small Magellanic Cloud |
| Full Description |
A NASA Hubble Space Telescope "family portrait" of young, ultra-bright stars nested in their embryonic cloud of glowing gases. The celestial maternity ward, called N81, is located 200,000 light-years away in the Small Magellanic Cloud (SMC), a small irregular satellite galaxy of our Milky Way. Hubble's exquisite resolution allows astronomers to pinpoint 50 separate stars tightly packed in the nebula's core within a 10 light- year diameter - slightly more than twice the distance between earth and the nearest star to our sun. The closest pair of stars is only 1/3 of a light-year apart (0.3 arcseconds in the sky). This furious rate of mass loss from these super-hot stars is evident in the Hubble picture that reveals dramatic shapes sculpted in the nebula's wall of glowing gases by violent stellar winds and shock waves. A pair of bright stars in the center of the nebula is pouring out most of the ultraviolet radiation to make the nebula glow. Just above them, a small dark knot is all that is left of the cold cloud of molecular hydrogen and dust the stars were born from. Dark absorption lanes of residual dust trisect the nebula. The nebula offers a unique opportunity for a close-up glimpse at the firestorm' accompanying the birth of extremely massive stars, each blazing with the brilliance of 300,000 of our suns. Such galactic fireworks were much more common billions of years ago in the early universe, when most star formation took place. The "natural- color" view was assembled from separate images taken with the Wide Field and Planetary Camera 2, in ultraviolet light and two narrow emission lines of ionized Hydrogen (H-alpha, H-beta). |
| Date |
09/24/1997 |
| NASA Center |
Hubble Space Telescope Center |
|
Nursery of New Stars
| Title |
Nursery of New Stars |
| Full Description |
This is a Hubble Space Telescope image (right) of a vast nebula called NGC 604, which lies in the neighboring spiral galaxy M33, located 2.7 million light-years away in the constellation Triangulum. This is a site where new stars are being born in a spiral arm of the galaxy. Though such nebulae are common in galaxies, this one is particularly large, nearly 1,500 light-years across. The nebula is so vast it is easily seen in ground-based telescopic images (left). At the heart of NGC 604 are over 200 hot stars, much more massive than our Sun (15 to 60 solar masses). They heat the gaseous walls of the nebula making the gas fluoresce. Their light also highlights the nebula's three-dimensional shape, like a lantern in a cavern. By studying the physical structure of a giant nebula, astronomers may determine how clusters of massive stars affect the evolution of the interstellar medium of the galaxy. The nebula also yields clues to its star formation history and will improve understanding of the starburst process when a galaxy undergoes a "firestorm" of star formation. The image was taken on January 17, 1995 with Hubble's Wide Field and Planetary Camera 2. Separate exposures were taken in different colors of light to study the physical properties of the hot gas (17,000 degrees Fahrenheit, 10,000 degrees Kelvin |
| Date |
01/17/1995 |
| NASA Center |
Hubble Space Telescope Center |
|
Peering into the Heart of th
…
| Title |
Peering into the Heart of the Crab Nebula |
| Full Description |
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 the "Guest 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 own Sun. Its life ended on July 4, 1054 when it exploded as a supernova. In this image, NASA's Hubble Space Telescope has zoomed in on the center of the Crab to reveal its structure with unprecedented detail. The Crab Nebula data were obtained by Hubble's Wide Field and Planetary Camera 2 in 1995. Images taken with five different color filters have been combined to construct this new false-color picture. Resembling an abstract painting by Jackson Pollack, the image shows ragged shards of gas that are expanding away from the explosion site at over 3 million miles per hour. The core of the star has survived the explosion as a pulsar, visible in the Hubble image as the lower of the two moderately bright stars to the upper left of center. The pulsar is a neutron star that spins on its axis 30 times a second. It heats its surroundings, creating the ghostly diffuse bluish-green glowing gas cloud in its vicinity, including a blue arc just to its right. The colorful network of filaments is the material from the outer layers of the star that was expelled during the explosion. The picture is somewhat deceptive in that the filaments appear to be close to the pulsar. In reality, the yellowish green filaments toward the bottom of the image are closer to us, and approaching at some 300 miles per second. The orange and pink filaments toward the top of the picture include material behind the pulsar, rushing away from us at similar speeds. The various colors in the picture arise from different chemical elements in the expanding gas, including hydrogen (orange), nitrogen (red), sulfur (pink), and oxygen (green). The shades of color represent variations in the temperature and density of the gas, as well as changes in the elemental composition. Kris Davidson (U. Minn.) led the research team of William P. Blair (JHU), Robert A. Fesen (Dartmouth), Alan Uomoto (JHU), Gordon M. MacAlpine (U. Mich.), and Richard B.C. Henry (U. Okla.) in the collection of the HST data. The Hubble Heritage Team created the color image from black and white data processed by Dr. Blair. |
| Date |
06/01/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
Butterfly Nebula
| Title |
Butterfly Nebula |
| Full Description |
The Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2) is back at work, capturing this image 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 binary star system at the nebula's center. The image was taken on March 6, 1997 as part of the recommissioning of the Hubble Space Telescope's previously installed scientific instruments following the successful servicing of the HST by NASA shuttle astronauts in February. WFPC2 was installed in HST during the servicing mission in 1993. At the center of the nebula lies a pair of stars that are so close together that they orbit around each other every 16 days. This is so close that, even with Hubble, the pair of stars cannot be resolved into its two components. One component of this binary is the hot core of a star that has ejected most of its outer layers, producing the surrounding nebula. Astronomers believe that this star, when it evolved and expanded to become a red giant, actually swallowed its companion star in an act of stellar cannibalism. The resulting interaction led to a spiraling together of the two stars, culminating in ejection of the outer layers of the red giant. Most of the outer layers were ejected into a dense disk, which can still be seen in the Hubble image, surrounding the central star. Later the hot star developed a fast stellar wind. This wind, blowing out into the surrounding disk, has inflated the large, wispy hourglass-shaped wings perpendicular to the disk. These wings produce the butterfly appearance when seen in projection. The total diameter of the nebula is about one-third of a light-year, or 2 trillion miles. |
| Date |
03/06/1997 |
| NASA Center |
Hubble Space Telescope Center |
|
Cometary Knots Around A Dyin
…
| Title |
Cometary Knots Around A Dying Star |
| Full Description |
These gigantic, tadpole-shaped objects are probably the result of a dying star's last gasps. Dubbed "cometary knots" because their glowing heads and gossamer tails resemble comets, the gaseous objects probably were formed during a star's final stages of life. Hubble astronomer C. Robert O'Dell and graduate student Kerry P. Handron of Rice University in Houston, Texas discovered thousands of these knots with the Hubble Space Telescope while exploring the Helix nebula, the closest planetary nebula to Earth at 450 light-years away in the constellation Aquarius. Although ground-based telescopes have revealed such objects, astronomers have never seen so many of them. The most visible knots all lie along the inner edge of the doomed star's ring, trillions of miles away from the star's nucleus. Although these gaseous knots appear small, they're actually huge. Each gaseous head is at least twice the size of our solar system, each tail stretches for 100 billion miles, about 1,000 times the distance between the Earth and the Sun. Astronomers theorize that the doomed star spews hot, lower-density gas from its surface, which collides with cooler, higher-density gas that had been ejected 10,000 years before. The crash fragments the smooth cloud surrounding the star into smaller, denser finger-like droplets, like dripping paint. This image was taken in August, 1994 with Hubble's Wide Field Planetary Camera 2. The red light depicts nitrogen emission ([NII] 6584A), green, hydrogen (H-alpha, 6563A), and blue, oxygen (5007A). |
| Date |
08/01/1994 |
| NASA Center |
Hubble Space Telescope Center |
|
Stellar
| Title |
Stellar |
| Full Description |
This eerie, dark structure, resembling an imaginary sea serpent's head, is a column of cool molecular hydrogen gas (two atoms of hydrogen in each molecule) and dust that is an incubator for new stars. The stars are embedded inside finger-like protrusions extending from the top of the nebula. Each "fingertip" is somewhat larger than our own solar system. The pillar is slowly eroding away by the ultraviolet light from nearby hot stars, a process called "photoevaporation." As it does, small globules of especially dense gas buried within the cloud is uncovered. These globules have been dubbed "EGGs" -- an acronym for "Evaporating Gaseous Globules." The shadows of the EGGs protect gas behind them, resulting in the finger-like structures at the top of the cloud. Forming inside at least some of the EGGs are embryonic stars -- stars that abruptly stop growing when the EGGs are uncovered and they are separated from the larger reservoir of gas from which they were drawing mass. Eventually the stars emerge, as the EGGs themselves succumb to photoevaporation. The stellar EGGS are found, appropriately enough, in the "Eagle Nebula" (also called M16 -- the 16th object in Charles Messier's 18th century catalog of "fuzzy" permanent objects in the sky), a nearby star-forming region 7,000 light-years away in the constellation Serpens. The picture was taken on April 1, 1995 with the Hubble Space Telescope Wide Field and Planetary Camera 2. The color image is constructed from three separate images taken in the light of emission from different types of atoms. Red shows emission from singly-ionized sulfur atoms. Green shows emission from hydrogen. Blue shows light emitted by doubly-ionized oxygen atoms. |
| Date |
4/1/1995 |
| NASA Center |
Hubble Space Telescope Center |
|
Stingray Nebula
| Title |
Stingray Nebula |
| Full Description |
This Wide Field and Planetary Camera 2 image captures the infancy of the Stingray nebula (Hen-1357), the youngest known planetary nebula. In this image, the bright central star is in the middle of the green ring of gas. Its companion star is diagonally above it at 10 o'clock. A spur of gas (green) is forming a faint bridge to the companion star due to gravitational attraction. The image also shows a ring of gas (green) surrounding the central star, with bubbles of gas to the lower left and upper right of the ring. The wind of material propelled by radiation from the hot central star has created enough pressure to blow open holes in the ends of the bubbles, allowing gas to escape. The red curved lines represent bright gas that is heated by a "shock" caused when the central star's wind hits the walls of the bubbles. The nebula is as large as 130 solar systems, but, at its distance of 18,000 light-years, it appears only as big as a dime viewed a mile away. The Stingray is located in the direction of the southern constellation Ara (the Altar). The colors shown are actual colors emitted by nitrogen (red), oxygen (green), and hydrogen (blue). |
| Date |
03/01/1996 |
| NASA Center |
Hubble Space Telescope Center |
|
Fireworks of Star Formation
…
| Title |
Fireworks of Star Formation Light Up a Galaxy |
| Full Description |
Located some 13 million light-years from Earth, NGC 4214 is currently forming clusters of new stars from its interstellar gas and dust. In this Hubble image, we can see a sequence of steps in the formation and evolution of stars and star clusters. The picture was created from exposures taken in several color filters with Hubble's Wide Field Planetary Camera 2. NGC 4214 contains a multitude of faint stars covering most of the frame, but the picture is dominated by filigreed clouds of glowing gas surrounding bright stellar clusters. The youngest of these star clusters are located at the lower right of the picture, where they appear as about half a dozen bright clumps of glowing gas. Young, hot stars have a whitish to bluish color in the Hubble image, because of their high surface temperatures, ranging from 10,000 up to about 50,000 degrees Celsius. The radiation and wind forces from the young stars literally blow bubbles in the gas. Over millions of years, the bubbles increase in size as the stars inside them grow older. Moving to the lower left from the youngest clusters, we find an older star cluster, around which a gas bubble has inflated to the point that there is an obvious cavity around the central cluster. The most spectacular feature in the Hubble picture lies near the center of NGC 4214. This object is a cluster of hundreds of massive blue stars, each of them more than 10,000 times brighter than our own Sun. A vast heart-shaped bubble, inflated by the combined stellar winds and radiation pressure, surrounds the cluster. The expansion of the bubble is augmented as the most massive stars in the center reach the ends of their lives and explode as supernovae. The principal astronomers are: John MacKenty, Jesus Maiz-Apellaniz (Space Telescope Science Institute), Colin Norman (Johns Hopkins University), Nolan Walborn (Space Telescope Science Institute), Richard Burg (Johns Hopkins University), Richard Griffiths (Carnegie Mellon University), and Rosemary Wyse (Johns Hopkins University). |
| Date |
01/06/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
First Picture of Mars
| Title |
First Picture of Mars |
| Full Description |
Sand dunes and large rocks are revealed in this panoramic image of Mars, the first photograph taken by Viking 1's Camera 1 on July 23, 1976. The horizon is approximately 3 kilometers (2 miles) away. The left and right thirds of the picture are the same area that were photographed on July 20 (Sol 0) by camera 2 and provide stereo coverage. The middle third reveals a part of the Martian Surface not seen on the July 20th panorama. The late afternoon sun is high in the sky over the left side of the picture. The support struts of the S-band high-gain antenna extends to the top of the picture. The American flags are located on the two RTG (Radioisotope Thermoeletric Generator) wind screens. In the middle third of the picture the rocky surface is covered by thick deposits of wind-blown material, forming numerous dunes. At the center of the picture on the horizon are two low hills which may be part of the rim of the distant crater. Two very large rocks are visible in the middle ground, the nearer one is 3 meters (10 feet) in diameter and is 8 meters (25 feets) from the spacecraft. A cloud layer is visible halfway between the horizon and the top of the picture. The meterology boom is located right of center. Behind it, the "White Mesa" is visible, which could be seen on the far left side of the Sol 0 Camera 2 panorama. In the nearer ground are numerous rocks about 10cm (4 inches) across, with horse-shoe shaped scour marks on their upwind side and wind tails in their lee. The fine grained material in the front of them contains small pits formed by impact of material kicked out by the lander's descent rocket engines. |
| Date |
07/23/1976 |
| NASA Center |
Headquarters |
|
Galactic Silhouettes
| Title |
Galactic Silhouettes |
| Full Description |
This new image from NASA's Hubble Space Telescope and its Wide Field and Planetary Camera 2 (WFPC2) shows the unique galaxy pair called NGC 3314. Through an extraordinary chance alignment, a face-on spiral galaxy lies precisely in front of another larger spiral. This line-up provides us with the rare chance to visualize dark material within the front galaxy, seen only because it is silhouetted against the object behind it. Dust lying in the spiral arms of the foreground galaxy stands out where it absorbs light from the more distant galaxy. This silhouetting shows us where the interstellar dust clouds are located, and how much light they absorb. The outer spiral arms of the front galaxy appear to change from bright to dark, as they are projected first against deep space, and then against the bright background of the other galaxy. NGC 3314 lies about 140 million light-years from Earth, in the direction of the southern hemisphere constellation Hydra. The bright blue stars forming a pinwheel shape near the center of the front galaxy have formed recently from interstellar gas and dust. A small, red patch near the center of the image is the bright nucleus of the background galaxy, NGC 3314b. It is reddened for the same reason the setting sun looks red. When light passes through a volume containing small particles (molecules in the Earth's atmosphere or interstellar dust particles in galaxies), its color becomes redder. The Hubble Heritage color image of NGC 3314 was constructed from archival images taken with WFPC2 in April 1999 by Drs. William Keel and Ray White III (University of Alabama) in blue and infrared light, combined with new images obtained by the Heritage team in March 2000 using blue, green and red filters. |
| Date |
05/11/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
Giant Twisters in the Lagoon
…
| Title |
Giant Twisters in the Lagoon Nebula |
| Full Description |
This NASA Hubble Space Telescope (HST) image reveals a pair of one-half light-year long interstellar "twisters," eerie funnels and twisted-rope structures in the heart of the Lagoon Nebula (Messier 8) which lies 5,000 light-years away in the direction of the constellation Sagittarius. The central hot star, O Herschel 36 (lower right), is the primary source of the ionizing radiation for the brightest region in the nebula, called the Hourglass. Analogous to the spectacular phenomena of Earth tornadoes, the large difference in temperature between the hot surface and cold interior of the clouds, combined with the pressure of starlight, may produce strong horizontal shear to twist the clouds into their tornado-like appearance. Though the spiral shapes suggest the clouds are "twisting," future observations will be needed, perhaps with Hubble's next generation instruments, with the spectroscopic capabilities of the Space Telescope Imaging Spectrograph (STIS) or the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), to actually measure velocities. These color-coded images are the combination of individual exposures taken in July and September, 1995 with Hubble's Wide Field and Planetary Camera 2 (WFPC2) through three narrow-band filters (red light ionized sulphur atoms, blue light, double ionized oxygen atoms, green light, ionized hydrogen). |
| Date |
09/27/1995 |
| NASA Center |
Hubble Space Telescope Center |
|
Supernova SN1987A in the Lar
…
| Title |
Supernova SN1987A in the Large Magellanic Cloud |
| Full Description |
Glittering stars and wisps of gas create a breathtaking backdrop for the self-destruction of a massive star, called supernova 1987A, in the Large Magellanic Cloud, a nearby galaxy. Astronomers in the Southern hemisphere witnessed the brilliant explosion of this star on Feb. 23, 1987. Shown in this NASA Hubble Space Telescope image, the supernova remnant, surrounded by inner and outer rings of material, is set in a forest of ethereal, diffuse clouds of gas. This three-color image is composed of several pictures of the supernova and its neighboring region taken with the Wide Field and Planetary Camera 2 in Sept. 1994, Feb. 1996 and July 1997. The many bright blue stars nearby the supernova are massive stars, each more than six times heftier than our Sun. They are members of the same generation of stars as the star that went supernova about 12 million years ago. The presence of bright gas clouds is another sign of the youth of this region, which still appears to be a fertile breeding ground for new stars. In a few years the supernova's fast moving material will sweep the inner ring with full force, heating and exciting its gas, and will produce a new series of cosmic fireworks that will offer a striking view for more than a decade. |
| Date |
02/04/1999 |
| NASA Center |
Hubble Space Telescope Center |
|
The Eagle Nebula
| Title |
The Eagle Nebula |
| Full Description |
These eerie, dark pillar-like structures are columns of cool interstellar hydrogen gas and dust that are also incubators for new stars. The pillars protrude from the interior wall of a dark molecular cloud like stalagmites from the floor of a cavern. They are part of the "Eagle Nebula" (also called M16 -- the 16th object in Charles Messier's 18th century catalog of "fuzzy" objects that aren't comets), a nearby star-forming region 7,000 light-years away in the constellation Serpens. Ultraviolet light is responsible for illuminating the convoluted surfaces of the columns and the ghostly streamers of gas boiling away from their surfaces, producing the dramatic visual effects that highlight the three dimensional nature of the clouds. The tallest pillar (left) is about a light-year long from base to tip. As the pillars themselves are slowly eroded away by the ultraviolet light, small globules of even denser gas buried within the pillars are uncovered. These globules have been dubbed "EGGs." EGGs is an acronym for "Evaporating Gaseous Globules," but it is also a word that describes what these objects are. Forming inside at least some of the EGGs are embryonic stars, stars that abruptly stop growing when the EGGs are uncovered and they are separated from the larger reservoir of gas from which they were drawing mass. Eventually, the stars themselves emerge from the EGGs as the EGGs themselves succumb to photoevaporation. The picture was taken on April 1, 1995 with the Hubble Space Telescope Wide Field and Planetary Camera 2. The color image is constructed from three separate images taken in the light of emission from different types of atoms. Red shows emission from singly-ionized sulfur atoms. Green shows emission from hydrogen. Blue shows light emitted by doubly- ionized oxygen atoms. |
| Date |
04/01/1995 |
| NASA Center |
Hubble Space Telescope Center |
|
The Glowing Eye of NGC 6751
| Title |
The Glowing Eye of NGC 6751 |
| Full Description |
Astronomers using NASA's Hubble Space Telescope have obtained images of the strikingly unusual planetary nebula, NGC 6751. Glowing in the constellation Aquila like a giant eye, the nebula is a cloud of gas ejected several thousand years ago from the hot star visible in its center. The Hubble observations were obtained in 1998 with the Wide Field and Planetary Camera 2 (WFPC2) by a team of astronomers led by Arsen Hajian of the U.S. Naval Observatory in Washington, DC. The Hubble Heritage team, working at the Space Telescope Science Institute in Baltimore, has prepared this color rendition by combining the Hajian team's WFPC2 images taken through three different color filters that isolate nebular gases of different temperatures. The nebula shows several remarkable and poorly understood features. Blue regions mark the hottest glowing gas, which forms a roughly circular ring around the central stellar remnant. Orange and red show the locations of cooler gas. The cool gas tends to lie in long streamers pointing away from the central star, and in a surrounding, tattered-looking ring at the outer edge of the nebula. The origin of these cooler clouds within the nebula is still uncertain, but the streamers are clear evidence that their shapes are affected by radiation and stellar winds from the hot star at the center. |
| Date |
04/06/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
The Reflection Nebula in Ori
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| Title |
The Reflection Nebula in Orion |
| Full Description |
Just weeks after NASA astronauts repaired the Hubble Space Telescope in December 1999, the Hubble Heritage Project snapped this picture of NGC 1999, a nebula in the constellation Orion. The Heritage astronomers, in collaboration with scientists in Texas and Ireland, used Hubble's Wide Field and Planetary Camera 2 (WFPC2) to obtain the color image. NGC 1999 is an example of a reflection nebula. Like fog around a street lamp, a reflection nebula shines only because the light from an imbedded source illuminates its dust, the nebula does not emit any visible light of its own. NGC 1999 lies close to the famous Orion Nebula, about 1,500 light-years from Earth, in a region of our Milky Way galaxy where new stars are being formed actively. NGC 1999 was discovered some two centuries ago by Sir William Herschel and his sister Caroline, and was cataloged later in the 19th century as object 1999 in the New General Catalogue. This data was collected in January 2000 by the Hubble Heritage Team with the collaboration of star-formation experts C. Robert O'Dell (Rice University), Thomas P. Ray (Dublin Institute for Advanced Study), and David Corcoran (University of Limerick). |
| Date |
03/02/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
The Ring Nebula
| Title |
The Ring Nebula |
| Full Description |
The NASA Hubble Space Telescope has captured the sharpest view yet of the most famous of all planetary nebulae, the Ring Nebula (M57). In this October 1998 image, the telescope has looked down a barrel of gas cast off by a dying star thousands of years ago. This photo reveals elongated dark clumps of material embedded in the gas at the edge of the nebula, the dying central star floating in a blue haze of hot gas. The nebula is about a light-year in diameter and is located some 2,000 light-years from Earth in the direction of the constellation Lyra. The colors are approximately true colors. The color image was assembled from three black-and-white photos taken through different color filters with the Hubble telescope's Wide Field and Planetary Camera 2. Blue isolates emission from very hot helium, which is located primarily close to the hot central star. Green represents ionized oxygen, which is located farther from the star. Red shows ionized nitrogen, which is radiated from the coolest gas, located farthest from the star. The gradations of color illustrate how the gas glows because it is bathed in ultraviolet radiation from the remnant central star, whose surface temperature is a white-hot 216,000 degrees Fahrenheit (120,000 degrees Celsius). |
| Date |
10/01/1998 |
| NASA Center |
Hubble Space Telescope Center |
|
Hubble Reopens Eye on the Un
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| Title |
Hubble Reopens Eye on the Universe |
| Full Description |
In its first glimpse of the heavens following the successful December 1999 servicing mission, NASA's Hubble Space Telescope captured a majestic view of a planetary nebula, the glowing remains of a dying, Sun-like star. This stellar relic, first spied by William Herschel in 1787, is nicknamed the "Eskimo" Nebula (NGC 2392) because, when viewed through ground-based telescopes, it resembles a face surrounded by a fur parka. In this Hubble telescope image, the "parka" is really a disk of material embellished with a ring of comet-shaped objects, with their tails streaming away from the central, dying star. The Eskimo's "face" also contains some fascinating details. Although this bright central region resembles a ball of twine, it is, in reality, a bubble of material being blown into space by the central star's intense "wind" of high-speed material. In this photo, one bubble lies in front of the other, obscuring part of the second lobe. Scientists believe that a ring of dense material around the star's equator, ejected during its red giant phase, created the nebula's shape. The bubbles are not smooth like balloons but have filaments of denser matter. Each bubble is about 1 light-year long and about half a light-year wide. Scientists are still puzzled about the origin of the comet-shaped features in the "parka." One possible explanation is that these objects formed from a collision of slow-and fast-moving gases. The Eskimo Nebula is about 5,000 light-years from Earth in the constellation Gemini. The picture was taken Jan. 10 and 11, 2000, with the Wide Field and Planetary Camera 2. The nebula's glowing gases produce the colors in this image: nitrogen (red), hydrogen (green), oxygen (blue), and helium (violet). |
| Date |
01/24/2000 |
| NASA Center |
Hubble Space Telescope Center |
|
The Twin Jet Nebula
| Title |
The Twin Jet Nebula |
| Full Description |
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. This is much the same process that takes place in a jet engine: The burning and expanding gases are deflected by the engine walls through a nozzle to form long, collimated jets of hot air at high speeds. M2-9 is 2,100 light-years away in the constellation Ophiucus. The observation was taken Aug. 2, 1997 by the Hubble telescope's Wide Field and Planetary Camera 2. In this image, neutral oxygen is shown in red, once-ionized nitrogen in green, and twice-ionized oxygen in blue. |
| Date |
12/17/1997 |
| NASA Center |
Hubble Space Telescope Center |
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