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Advanced Communication Technology Satellite (ACTS) and Sun of Jet Propulsion Laboratory (JPL)
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Band of Rubble
| Title |
Band of Rubble |
| Description |
This artist's animation illustrates a massive asteroid belt in orbit around a star the same age and size as our Sun. Evidence for this possible belt was discovered by NASA's Spitzer Space Telescope when it spotted warm dust around the star, presumably from asteroids smashing together. The view starts from outside the belt, where planets like the one shown here might possibly reside, then moves into to the dusty belt itself. A collision between two asteroids is depicted near the end of the movie. Collisions like this replenish the dust in the asteroid belt, making it detectable to Spitzer. The alien belt circles a faint, nearby star called HD 69830 located 41 light-years away in the constellation Puppis. Compared to our own solar system's asteroid belt, this one is larger and closer to its star -- it is 25 times as massive, and lies just inside an orbit equivalent to that of Venus. Our asteroid belt circles between the orbits of Mars and Jupiter. Because Jupiter acts as an outer wall to our asteroid belt, shepherding its debris into a series of bands, it is possible that an unseen planet is likewise marshalling this belt's rubble. Previous observations using the radial velocity technique did not locate any large gas giant planets, indicating that any planets present in this system would have to be the size of Saturn or smaller. Asteroids are chunks of rock from "failed" planets, which never managed to coalesce into full-sized planets. Asteroid belts can be thought of as construction sites that accompany the building of rocky planets. |
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It's a Rocky World
| Title |
It's a Rocky World |
| Description |
This artist's concept show a massive asteroid belt in orbit around a star the same age and size as our Sun. Evidence for this possible belt was discovered by NASA's Spitzer Space Telescope when it spotted warm dust around the star, presumably from asteroids smashing together. The view is from outside the belt, where planets like the one shown in the foreground, might possibly reside. A collision between two asteroids is depicted to the right. Collisions like this replenish the dust in the asteroid belt, making it detectable to Spitzer. The alien belt circles a faint, nearby star called HD 69830 located 41 light-years away in the constellation Puppis. Compared to our own solar system's asteroid belt, this one is larger and closer to its star -- it is 25 times as massive, and lies just inside an orbit equivalent to that of Venus. Our asteroid belt circles between the orbits of Mars and Jupiter. Because Jupiter acts as an outer wall to our asteroid belt, shepherding its debris into a series of bands, it is possible that an unseen planet is likewise marshalling this belt's rubble. Previous observations using the radial velocity technique did not locate any large gas giant planets, indicating that any planets present in this system would have to be the size of Saturn or smaller. Asteroids are chunks of rock from "failed" planets, which never managed to coalesce into full-sized planets. Asteroid belts can be thought of as construction sites that accompany the building of rocky planets. |
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Veil of Ice
| Description |
Veil of Ice |
| Full Description |
The Cassini spacecraft stares toward Saturn through its gauzy veil of rings. The great ice-particle screen acts like a filter here, attenuating the glare from the planet and making its high altitude haze easy to see. The F ring shows off the faint ringlets flanking its core, and a single ringlet can be seen in the Encke Gap, crossing through center. This view looks toward the unlit side of the rings from about 18 degrees above the ringplane. The image was taken in visible blue light with the Cassini spacecraft narrow-angle camera on Nov. 4, 2006 at a distance of approximately 1.7 million kilometers (1 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 161 degrees. Image scale is 10 kilometers (6 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/Space Science Institute |
| Date |
January 12, 2007 |
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Planet Temperatures
| title |
Planet Temperatures |
| description |
In general, the surface temperature of the planets decreases with increasing distance from the Sun. Venus is an exception because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead (3280C). Mercury rotates slowly and has a thin atmosphere, and consequently, the nightside temperature can be more than 5000C lower than the dayside temperature shown on the diagram. Temperatures for the gas giants (Jupiter, Saturn, Uranus, and Neptune) are shown at a level in the atmosphere equal in pressure to sea level on Earth. Temperatures are in both Fahrenheit and Celsius, and the planets are not shown to scale. *Image Credit*: Lunar and Planetary Institute |
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Veil of Ice
PIA08853
Saturn
Imaging Science Subsystem -
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| Title |
Veil of Ice |
| Original Caption Released with Image |
The Cassini spacecraft stares toward Saturn through its gauzy veil of rings. The great ice-particle screen acts like a filter here, attenuating the glare from the planet and making its high altitude haze easy to see. The F ring shows off the faint ringlets flanking its core, and a single ringlet can be seen in the Encke Gap, crossing through center. This view looks toward the unlit side of the rings from about 18 degrees above the ringplane. The image was taken in visible blue light with the Cassini spacecraft narrow-angle camera on Nov. 4, 2006 at a distance of approximately 1.7 million kilometers (1 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 161 degrees. Image scale is 10 kilometers (6 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm [ http://saturn.jpl.nasa.gov ]. The Cassini imaging team homepage is at http://ciclops.org [ http://ciclops.org ]. |
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Measurements of the Martian
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PIA01340
Sol (our sun)
Thermal Emission Spectromete
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| Title |
Measurements of the Martian Winds for Three Seasons |
| Original Caption Released with Image |
Observations (from the Thermal Emission Spectrometer, or TES, instrument)covering one half martian year allow us to follow the development of the northern winter polar vortex. This high speed west wind builds up from fall ("early October" in a calendar seasonally equivalent to the terrestrial calendar) to maximum strength in winter ("late December"). As spring approaches ("late March"), it gradually declines. At maximum strength its winds exceed 160 m/s (360 miles per hour). It also acts as an effective barrier to the northward transport of atmospheric dust, during its most active phase, only condensates (water and CO2 ices) were observed in its core. Detailed study of this effect is important to determine the accumulation of deposits on the permanent polar cap. The TES instrument was built by Santa Barbara Remote Sensing and is operated by Philip R. Christensen, of Arizona State University, Tempe, AZ. The MGS mission is managed for NASA by the Jet Propulsion Laboratory, Pasadena CA. |
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Auqakuh Valles
PIA03824
Sol (our sun)
Thermal Emission Imaging Sys
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| Title |
Auqakuh Valles |
| Original Caption Released with Image |
(Released 7 June 2002) The Science This ancient sinuous river channel, located near 30° N, 299° W (61° E), was likely carved by water early in Mars history. Auqakuh Valles cuts through a remarkable series of rock layers that were deposited and then subsequently eroded. This change from conditions favoring deposition to those favoring erosion indicates that the environment of this region has changed significantly over time. In addition, the different rock layers seen in this image vary in hardness, with some being relatively soft and easily eroded, whereas others are harder and resistant. These differences imply that these layers vary in their composition, physical properties, and/or degree of cementation, and again suggest that major changes have occurred during the history of this region. Similar differences occur throughout the southwest U.S., where hard rock layers, such as the limestones and sandstones in the Grand Canyon, form resistant cliffs, whereas softer mudstones are easily eroded to form broad slopes. The Martian layers, such as the smooth, dark-toned mesas visible in numerous places to the right (east) of the channel, were once continuous across the region. As these layers have eroded, they have produced a wide array of textures, from smooth surfaces, to knobby terrains, to the unusual lobate patterns seen in the upper right of the image. The most recent activity in the region appears to be the formation of mega-ripples by the wind. These ripples, spaced approximately 75 m apart, form perpendicular to the wind direction, and can be seen following the pattern of the channel floor as it curves through this region. This pattern shows that even this relatively small channel, which varies in width from about 500 to 750 m throughout this image, acts to funnel the wind down the channel. The Story Auqakuh Vallis, an ancient river channel that winds its way down the center of this image, is the "fossil" remains of an earlier, probably more watery time in Martian history. Now, you might think that Auqakuh has something to do with Aqua, the Latin word for water. Instead, Auqakuh is the word for Mars in the Quechuan language of the Incan Empire that once stretched across vast portions of South America. This Inca-honoring river channel cuts through a remarkable series of rock layers that expose a history of climate change in the region. The coarse, rugged, and wildly textured terrain was created as rock layers were first deposited, then eroded over time. Some of the rock layers are soft and easily eroded, while others are clearly harder and more resistant. From these differences, geologists can tell that the layers are made up of different materials, have different physical characteristics, and are either loosely or strongly cemented together. That suggests major environmental changes over time as well, since different kinds of rocks form under different conditions. Similar differences in rock layers occur throughout the Southwest of the, United States. The next time you're visiting the Grand Canyon or hiking in similar terrain, notice where hard rock layers, such as limestones and sandstones, form resistant cliffs, whereas softer mudstones are easily eroded to form broad slopes along the canyon. Just in case the river channel in the above image looks more like a raised vein rather than a hollowed out channel, try looking at the half-circle depression on the left-hand side of the image, about a third of the way up. The bright features on the upper half streak down toward the bottom of the bowl. Once you focus on this for a while, your brain figures out that the channel must be depressed as well. Now that you can see that the channel cuts into the surface, click on the image for a closer look at the bottom of the channel. Mega-ripples about 82 yards apart line the channel floor as it curves through the region. This pattern shows that even this relatively small channel, which varies from about one-third to a half of a mile in width, funnels the wind down its curving length, creating perpendicular piles of waving texture on the channel's floor. East of the channel, smooth, dark-toned mesas are visible, providing a scant reminder that they were once continuous across the region. As these layers have eroded, they've produced a wide array of textures, from smooth surfaces, to knobby terrains, to the unusual curved, lobe-like patterns seen in the upper right of the image. |
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Auqakuh Valles
PIA03824
Sol (our sun)
Thermal Emission Imaging Sys
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| Title |
Auqakuh Valles |
| Original Caption Released with Image |
(Released 7 June 2002) The Science This ancient sinuous river channel, located near 30° N, 299° W (61° E), was likely carved by water early in Mars history. Auqakuh Valles cuts through a remarkable series of rock layers that were deposited and then subsequently eroded. This change from conditions favoring deposition to those favoring erosion indicates that the environment of this region has changed significantly over time. In addition, the different rock layers seen in this image vary in hardness, with some being relatively soft and easily eroded, whereas others are harder and resistant. These differences imply that these layers vary in their composition, physical properties, and/or degree of cementation, and again suggest that major changes have occurred during the history of this region. Similar differences occur throughout the southwest U.S., where hard rock layers, such as the limestones and sandstones in the Grand Canyon, form resistant cliffs, whereas softer mudstones are easily eroded to form broad slopes. The Martian layers, such as the smooth, dark-toned mesas visible in numerous places to the right (east) of the channel, were once continuous across the region. As these layers have eroded, they have produced a wide array of textures, from smooth surfaces, to knobby terrains, to the unusual lobate patterns seen in the upper right of the image. The most recent activity in the region appears to be the formation of mega-ripples by the wind. These ripples, spaced approximately 75 m apart, form perpendicular to the wind direction, and can be seen following the pattern of the channel floor as it curves through this region. This pattern shows that even this relatively small channel, which varies in width from about 500 to 750 m throughout this image, acts to funnel the wind down the channel. The Story Auqakuh Vallis, an ancient river channel that winds its way down the center of this image, is the "fossil" remains of an earlier, probably more watery time in Martian history. Now, you might think that Auqakuh has something to do with Aqua, the Latin word for water. Instead, Auqakuh is the word for Mars in the Quechuan language of the Incan Empire that once stretched across vast portions of South America. This Inca-honoring river channel cuts through a remarkable series of rock layers that expose a history of climate change in the region. The coarse, rugged, and wildly textured terrain was created as rock layers were first deposited, then eroded over time. Some of the rock layers are soft and easily eroded, while others are clearly harder and more resistant. From these differences, geologists can tell that the layers are made up of different materials, have different physical characteristics, and are either loosely or strongly cemented together. That suggests major environmental changes over time as well, since different kinds of rocks form under different conditions. Similar differences in rock layers occur throughout the Southwest of the, United States. The next time you're visiting the Grand Canyon or hiking in similar terrain, notice where hard rock layers, such as limestones and sandstones, form resistant cliffs, whereas softer mudstones are easily eroded to form broad slopes along the canyon. Just in case the river channel in the above image looks more like a raised vein rather than a hollowed out channel, try looking at the half-circle depression on the left-hand side of the image, about a third of the way up. The bright features on the upper half streak down toward the bottom of the bowl. Once you focus on this for a while, your brain figures out that the channel must be depressed as well. Now that you can see that the channel cuts into the surface, click on the image for a closer look at the bottom of the channel. Mega-ripples about 82 yards apart line the channel floor as it curves through the region. This pattern shows that even this relatively small channel, which varies from about one-third to a half of a mile in width, funnels the wind down its curving length, creating perpendicular piles of waving texture on the channel's floor. East of the channel, smooth, dark-toned mesas are visible, providing a scant reminder that they were once continuous across the region. As these layers have eroded, they've produced a wide array of textures, from smooth surfaces, to knobby terrains, to the unusual curved, lobe-like patterns seen in the upper right of the image. |
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Dust Devil Tracks
PIA03791
Sol (our sun)
Thermal Emission Imaging Sys
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| Title |
Dust Devil Tracks |
| Original Caption Released with Image |
(Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called |
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TOPEX/El Niño Watch - La Niñ
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PIA01525
Sol (our sun)
Altimeter
| Title |
TOPEX/El Niño Watch - La Niña Weakening, January 17, 1999 |
| Original Caption Released with Image |
This image of the Pacific Ocean was produced using sea-surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on January 17, 1999, sea surface height is an indicator of the heat content of the ocean. This image shows that the unusual large-scale warming (shown here in red and white) in the northwest Pacific that was first observed by the satellite in November 1998 has increased in size and spread east to the central Pacific and south to the equator. The low sea level or cold pool of water along the equator, commonly referred to as La Niña (shown in purple), has weakened in size and heat content during the last several months. Although weakening, the La Niña pattern continues to exert a strong influence on the worldwide climate system. According to oceanographers, the cold La Niña water acts like a boulder in a stream, steering the planet's prevailing winds and changing the course of storms that are born over the ocean. Equally important to North America's winter weather is the very large area of unusually warm Western Pacific ocean. Although the appearance of this feature is not fully understood or anticipated, it is adding energy to the winter storms coming out of the North Pacific which is fueling the very volatile weather over the continental U.S. In this image, the white areas show the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal, in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions. The purple areas are 14 to 18 centimeters (6 to 7 inches) below normal and the blue areas are 5 to 13 centimeters (2 to 5 inches) below normal. For more information, please visit the TOPEX/Poseidon project web page at http://topex-www.jpl.nasa.gov |
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Breakup of the World's Large
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PIA04344
Sol (our sun)
Multi-angle Imaging SpectroR
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| Title |
Breakup of the World's Largest Iceberg |
| Original Caption Released with Image |
Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60° forward-viewing, nadir, and 60° backward-viewing cameras are displayed as red, green and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology. |
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Band of Rubble
PIA07854
| Title |
Band of Rubble |
| Original Caption Released with Image |
This artist's animation illustrates a massive asteroid belt in orbit around a star the same age and size as our Sun. Evidence for this possible belt was discovered by NASA's Spitzer Space Telescope when it spotted warm dust around the star, presumably from asteroids smashing together. The view starts from outside the belt, where planets like the one shown here might possibly reside, then moves into to the dusty belt itself. A collision between two asteroids is depicted near the end of the movie. Collisions like this replenish the dust in the asteroid belt, making it detectable to Spitzer. The alien belt circles a faint, nearby star called HD 69830 located 41 light-years away in the constellation Puppis. Compared to our own solar system's asteroid belt, this one is larger and closer to its star - it is 25 times as massive, and lies just inside an orbit equivalent to that of Venus. Our asteroid belt circles between the orbits of Mars and Jupiter. Because Jupiter acts as an outer wall to our asteroid belt, shepherding its debris into a series of bands, it is possible that an unseen planet is likewise marshalling this belt's rubble. Previous observations using the radial velocity technique did not locate any large gas giant planets, indicating that any planets present in this system would have to be the size of Saturn or smaller. Asteroids are chunks of rock from "failed" planets, which never managed to coalesce into full-sized planets. Asteroid belts can be thought of as construction sites that accompany the building of rocky planets. |
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Entering Saturn's Magnetosph
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PIA06347
Sol (our sun)
Radio and Plasma Wave Scienc
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| Title |
Entering Saturn's Magnetosphere with a Boom |
| Original Caption Released with Image |
This graph illustrates the series of sonic booms that took place when the Cassini spacecraft crossed Saturn's bow shock. A bow shock is a shock wave located where incoming solar wind meets a planet's magnetosphere, or magnetic bubble. Differences in electrical charges cause the solar wind to curve around the magnetosphere in the same way that air flows around a supersonic airplane. The resulting turbulence is heard as a sonic boom and is represented here as an increase in wave frequency. Scientists were surprised to discover that Saturn's bow shock was located at a distance of 3 million kilometers (1.9 million miles) from Saturn, much farther out than they had predicted. Because the bow shock acts like a balloon when hit, oscillating in and out, Cassini actually crossed it several times, resulting in the seven sonic booms depicted above. Red denotes louder waves, and blue quieter. This data was taken by Cassini's radio and plasma wave science instrument. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radio and plasma wave science instrument team is based at the University of Iowa, Iowa City. For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov/ ] and the instrument team's home page, http://www-pw.physics.uiowa.edu/plasma-wave/cassini/home.html/ [ http://www-pw.physics.uiowa.edu/plasma-wave/cassini/home.html/ ]. |
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Bending the Rings
PIA06656
Sol (our sun)
Imaging Science Subsystem -
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| Title |
Bending the Rings |
| Original Caption Released with Image |
Saturn's rings appear strangely warped in this view of the rings seen through the upper Saturn atmosphere. The atmosphere acts like a lens in refracting (bending) the light reflected from the rings. As the rings pass behind the overexposed limb (edge) of Saturn as seen from Cassini, the ring structure appears to curve downward due to the bending of the light as it passes through the upper atmosphere. This image was obtained using a near-infrared filter. The filter samples a wavelength where methane gas does not absorb light, thus making the far-off rings visible through the upper atmosphere. By comparing this image to similar ones taken using filters where methane gas does absorb, scientists can estimate the vertical profile of haze and the abundance of methane in Saturn's high atmosphere. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 14, 2005, through a filter sensitive to wavelengths of infrared light centered at 938 nanometers and at a distance of approximately 197,000 kilometers (123,000 miles) from Saturn. The image scale is 820 meters (2,680 feet) per pixel. |
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SeaWinds - South Georgia Isl
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PIA02457
Sol (our sun)
SeaWinds Scatterometer
| Title |
SeaWinds - South Georgia Island |
| Original Caption Released with Image |
Winds are blocked by an island mountain barrier that produces a long "shadow" of low winds on the downwind side of the island stretching for hundreds of kilometers (about 500 miles long) in this image produced from data from NASA's SeaWinds instrument on the QuikScat satellite. South Georgia Island, in the South Atlantic Ocean (approximately 1,500 kilometers, or miles, east of the Falkland/Malvinas Islands, is only 170 kilometers long (about 106 miles) and 30 kilometers (about 19 miles)wide, but contains 13 peaks exceeding 2,000 meters (more than 6,500 feet) in height. The island thus acts as a significant barrier to the surface winds in this forbidding part of the world oceans. Mountainous islands and steep coastal topography can modify the surface wind field for many hundreds of kilometers seaward. The detailed air-sea-land interaction processes involved are not well understood, largely because of a lack of accurate, high-resolution, extensive wind speed and direction measurements. The broad-swath, all-weather SeaWinds instrument on NASA's QuikScat satellite is providing unique measurements of ocean winds, revealing previously unknown wind patterns caused by island topography and allowing development of improved models for coastal ocean winds. This image shows QuikScat measurements of wind speed and direction during a single pass over South Georgia Island on September 13, 1999. The island itself is shown as black (for heights less than 750 meters(less than half a mile), green (for heights between 750 and 1,500 meters (less than half a mile to about one mile), and red (for regions greater than 1,500 meters, or about one mile in altitude). The white area surrounding the island represents the region where land contamination does not allow wind measurements to be made. The horizontal and vertical coordinates are in kilometers, with origin on the island at latitude 54.5 degrees south, longitude 30 degrees east. This large-scale view shows regions of high wind speed off both the eastern and western ends of islands, corresponding to "corner accelerations" as the winds stream by the steep island topography. The lowest wind speeds are seen to be in the lee of the highest island topography. NASA's Earth Science Enterprise is a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system. JPL is a division of the California Institute of Technology, Pasadena, CA. |
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Black Hole Grabs Starry Snac
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PIA01884
| Title |
Black Hole Grabs Starry Snack |
| Original Caption Released with Image |
Poster Version 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. The artist's concept chronicles the star being ripped apart and swallowed by the cosmic beast over time. First, the intact sun-like star (left) ventures too close to the black hole, and its own self-gravity is overwhelmed by the black hole's gravity. The star then stretches apart (middle yellow blob) and eventually breaks into stellar crumbs, some of which swirl into the black hole (cloudy ring at right). This doomed material heats up and radiates light, including ultraviolet light, before disappearing forever into the black hole. The Galaxy Evolution Explorer was able to watch this process unfold by observing changes in ultraviolet light. The area around the black hole appears warped because the gravity of the black hole acts like a lens, twisting and distorting light. |
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Black Hole Grabs Starry Snac
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PIA01884
| Title |
Black Hole Grabs Starry Snack |
| Original Caption Released with Image |
Poster Version 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. The artist's concept chronicles the star being ripped apart and swallowed by the cosmic beast over time. First, the intact sun-like star (left) ventures too close to the black hole, and its own self-gravity is overwhelmed by the black hole's gravity. The star then stretches apart (middle yellow blob) and eventually breaks into stellar crumbs, some of which swirl into the black hole (cloudy ring at right). This doomed material heats up and radiates light, including ultraviolet light, before disappearing forever into the black hole. The Galaxy Evolution Explorer was able to watch this process unfold by observing changes in ultraviolet light. The area around the black hole appears warped because the gravity of the black hole acts like a lens, twisting and distorting light. |
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Mars Researchers Rendezvous
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PIA03714
Sol (our sun)
Multi-angle Imaging SpectroR
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| Title |
Mars Researchers Rendezvous on Remote Arctic Island |
| Original Caption Released with Image |
Devon Island is situated in an isolated part of Canada's Nunavut Territory, and is usually considered to be the largest uninhabited island in the world. However, each summer since 1999, researchers from NASA's Haughton-Mars Project and the Mars Society reside at this "polar desert" location to study the geologic and environmental characteristics of a site which is considered to be an excellent "Mars analog": a terrestrial location wherein specific conditions approximate environmental features reported on Mars. Base camps established amidst the rocks and rubble surrounding the Haughton impact crater enable researchers to conduct surveys designed to test the habitat, equipment and technology that may be deployed during a human mission to Mars. One of the many objectives of the project scientists is to understand the ice formations around the Haughton area, in the hopes that this might ultimately assist with the recognition of areas where ice can be found at shallow depth on Mars. These images of Devon Island from NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument provide contrasting views of the spectral and angular reflectance "signatures" of different surfaces within the region. The top panel is a natural color view created with data from the red, green and blue-bands of MISR's nadir (vertical-viewing) camera. The bottom panel is a false-color multiangular composite of the same area, utilizing red band data from MISR's 60-degree backward, nadir, and 60-degree forward-viewing cameras, displayed as red, green and blue, respectively. In this representation, colors highlight textural properties of elements within the scene, with blue tones indicating smooth surfaces (which preferentially forward scatter sunlight) and red hues indicating rougher surfaces (which preferentially backscatter). The angular reflectance "signature" of low clouds causes them to appear purple, and this visualization provides a unique way of distinguishing clouds from snow and ice. The data were captured on June 28, 2001, during the early part of the arctic summer, when sea ice becomes thinner and begins to move depending upon localized currents and winds. In winter the entire region is locked with several meters of nearly motionless sea ice, which acts as a thermodynamic barrier to the loss of heat from the comparatively warm ocean to the colder atmosphere. Summer melting of sea ice can be observed at the two large, dark regions of open water, one is present in the Jones Sound (near the top to the left of center), and another appears in the Wellington Channel (left-hand edge). A large crack caused by tidal heaving has broken the ice cover over the Parry Channel (lower right-hand corner). A substantial ice cap permanently occupies the easternmost third of the island (upper right). Surface features such as dendritic meltwater channels incised into the island's surface are apparent. The Haughton-Mars project site is located slightly to the left and above image, center, in an area which appears with relatively little surface ice, near the island's inner "elbow." The images were acquired during Terra orbit 8132 and cover an area of about 334 kilometers x 229 kilometers. They utilize data from blocks 27 to 31 within World Reference System-2 path 42. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology. |
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Clouds and Ice of the Lamber
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PIA03734
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Clouds and Ice of the Lambert-Amery System, East Antarctica |
| Original Caption Released with Image |
These views from the Multi-angle Imaging SpectroRadiometer (MISR) illustrate ice surface textures and cloud-top heights over the Amery Ice Shelf/Lambert Glacier system in East Antarctica on October 25, 2002. The left-hand panel is a natural-color view from MISR's downward-looking (nadir) camera. The center panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60° forward-viewing, nadir and 60° backward-viewing cameras are displayed as red, green and blue, respectively. With this display technique, surfaces which predominantly exhibit backward-scattering (generally rough surfaces) appear red/orange, while surfaces which predominantly exhibit forward-scattering (generally smooth surfaces) appear blue. Textural variation for both the grounded and sea ice are apparent. The red/orange pixels in the lower portion of the image correspond with a rough and crevassed region near the grounding zone, that is, the area where the Lambert and four other smaller glaciers merge and the ice starts to float as it forms the Amery Ice Shelf. In the natural-color view, this rough ice is spectrally blue in color. Clouds exhibit both forward and backward-scattering properties in the middle panel and thus appear purple, in distinct contrast with the underlying ice and snow. An additional multi-angular technique for differentiating clouds from ice is shown in the right-hand panel, which is a stereoscopically derived height field retrieved using automated pattern recognition involving data from multiple MISR cameras. Areas exhibiting insufficient spatial contrast for stereoscopic retrieval are shown in dark gray. Clouds are apparent as a result of their heights above the surface terrain. Polar clouds are an important factor in weather and climate. Inadequate characterization of cloud properties is currently responsible for large uncertainties in climate prediction models. Identification of polar clouds, mapping of their distributions, and retrieval of their heights provide information that will help to reduce this uncertainty. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 15171. The panels cover an area of 380 kilometers x 984 kilometers, and utilize data from blocks 145 to 151 within World Reference System-2 path 127. MISR was built and is managed by NASA's Jet Propulsion Laboratory,Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center,Greenbelt, MD. JPL is a division of the California Institute of Technology. |
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Changing Lightning Storms on
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PIA01636
Sol (our sun)
Solid-State Imaging
| Title |
Changing Lightning Storms on Jupiter |
| Original Caption Released with Image |
This view shows lightning storms in three different locations (panels 1, 2, and 3) on Jupiter's night side. Each panel shows multiple lightning strikes, coming from different parts of the same storm. The lightning originates in Jupiter's water cloud, which is 50 to 75 kilometers (30 to 45 miles) below the ammonia cloud. The latter acts as a translucent screen, diffusing the light over an area comparable to the depth. The individual strikes are unresolved in these images, which have a resolution of 133 kilometers (80 miles) per picture element. The brightest strikes emit as much light energy as 30 million 100-watt light bulbs burning for one second, which makes the strikes hundreds of times brighter than lightning on Earth. The bottom row shows the same three storms as the top row but the bottom-row images were taken two minutes later. The images were taken in the clear filter with an exposure time of 90 seconds. Clouds, illuminated by light reflected off Jupiter's moon Io, can be seen in the background. Moonlight on Jupiter is 100,000 times fainter than sunlight, and the lightning flashes would be undetectable on the day side of the planet. North is at the top of the picture. The planetocentric latitudes and west longitudes (in degrees) of the storms in panels 1 through 3 are (34.4, 16.1), (23.4, 27.6), and (8.6, 15.6), respectively. The panels are 8,000 kilometers (5,000 miles) on a side. The images in the top row were taken on October 6, 1997 at Universal Times (in hours:minutes:seconds), of 00:15:01, 00:17:03, and 00:17:03, respectively, by the solid state imaging camera system onboard NASA's Galileo spacecraft. Distance from the planet to the spacecraft was 6.62 million kilometers (4.1 million miles). JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ] . Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo [ http://www.jpl.nasa.gov/galileo/sepo ] . |
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Jovian Lightning and the Day
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PIA01638
Sol (our sun)
Solid-State Imaging
| Title |
Jovian Lightning and the Daytime Storm |
| Original Caption Released with Image |
This picture highlights a convective storm (left panel) and the associated lightning (right panels) in Jupiter's atmosphere. The left image shows the dayside view. The right images show the area highlighted (box) in the dayside view as it appeared 110 minutes later during the night. Multiple lightning strikes are visible in the night side images, which were taken 3 minutes and 38 seconds apart. The bright, cloudy area in the dayside view is similar in appearance to a region of upwelling in Earth's atmosphere. The dark, clear region to the west (left) appears similar to a region of downwelling in Earth's atmosphere. The presence of lightning confirms that this is a site of moist convection. The lightning originates below the visible ammonia cloud, which acts as a translucent screen, diffusing the light over a wider area. This apparent width can be used to infer the depth of approximately 75 kilometers (46 miles). This figure is consistent with the hypothesis that lightning originates in the Jovian water cloud at about 75 kilometers (46 miles) depth. To show details of the lightning, the nightside images have been expanded by a factor of two relative to the dayside image. The latitude and longitude scale is shown around the left panel. On Jupiter, one degree of latitude spans a distance of 1,200 kilometers (744 miles), so the highlighted area is approximately 2,400 kilometers (1,488 miles) on a side. The resolution is 23 kilometers (14 miles) per picture element. The dayside image was taken through the 727 nanometer filter with an exposure of 0.529 seconds at 23:03:03 Universal Time on November 7, 1997. The upper night side image was taken through the red filter with an exposure of 166.9 seconds in gain state 1 at 00:49:590 Universal Time on November 8, 1997. The bottom night side image was taken through the red filter with an exposure of 38.9 seconds in gain state 2 at 00:53:37 Universal Time on November 8, 1997. The signal to noise ratio is greater in the lower night side image because the gain state is higher. The images were taken by the solid state imaging camera system on NASA's Galileo spacecraft at a range of 1.1 million kilometers (680,000 miles). JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web on the Galileo mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ] . Background information and educational context for the images can be found at http://www.jpl.nas a.gov/galileo/sepo [ http://www.jpl.nasa.gov/galileo/sepo ]. |
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Candor Chasma
PIA03838
Sol (our sun)
Thermal Emission Imaging Sys
…
| Title |
Candor Chasma |
| Original Caption Released with Image |
(Released 27 June 2002) The Science This THEMIS visible image shows the effects of erosion on a beautiful sequence of dramatically layered rocks within Candor Chasma, which is part of the Valles Marineris. These layers were initially deposited within Candor, and have subsequently been eroded by a variety of processes, including wind and downslope motion due to gravity. The effect of erosion is manifest differently in the different layers and at different locations within the layered material. For example, the upper portion of the Candor deposit seen in the lower one-third of the image appears more intact, whereas downslope there is pronounced fluting to create produced "spur and gully" slopes. Relatively dark materials are seen throughout the image and appear to mantle select areas of the layered deposits. When seen in other areas by THEMIS, and at higher resolution by the Mars Global Surveyor camera, these dark materials often form sand dunes. The dark mantling material in Candor is likely dark sand as well. Several particularly dark patches can be seen near the left (western) edge of the image, approximately one quarter of the way up from the bottom of the image. Very few impact craters of any size can be seen in this image, indicating that the erosion and transport of material is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded. The Story The smooth, triangular shape near the center of this image is the plateau of a canyon, with walls that dramatically descend on either side. This canyon is named Chasma, which means "blaze" or "white" in Latin. The lighter, brighter material of the southern canyon wall displays erosional streaks that almost do happen to look like a white blaze. Toward the bottom left of the image, you can see how the relatively brighter material from the top has been carried down to the bottom. Notice that the upper, grayer part of the southern canyon walls don't seem to have the same erosional flutes as the brighter material just below it. By looking at such differences on the same canyon wall, geologists can begin to understand the kinds of materials that make up each layer of the canyon wall, and how resistant each is to erosion. No matter what part of the canyon you look at, erosion has created the beautiful sequence of layered rocks within Candor. Sometimes it's the wind that acts, and sometimes gravity, which pulls material from the upper parts of the canyon downslope. Be sure to click on the above image for a close-up view of all of the subtle layers and ripples. Look also for some dark, almost black patches (bottom left, about a quarter of the way up). These dark splotches are most likely made of sand. In fact, much of the darker areas seen in this image are probably made of sand. The sand often forms in dunes, as both THEMIS and the higher resolution camera on Mars Global Surveyor, Odyssey's sister orbiter, have shown. With all of the wind and downslope erosion,, , this area is fairly active geologically. You can tell because there are very few impact craters of any size to be seen. That means material is being transported at a rate that's rapid enough to bury or erode any craters that do form. Candor Chasma is part of Valles Marineris, the large canyon system that slices across a large part of the red planet. If Valles Marineris were located on Earth, it would stretch all the way from the west coast to the east coast of the United States. |
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Candor Chasma
PIA03838
Sol (our sun)
Thermal Emission Imaging Sys
…
| Title |
Candor Chasma |
| Original Caption Released with Image |
(Released 27 June 2002) The Science This THEMIS visible image shows the effects of erosion on a beautiful sequence of dramatically layered rocks within Candor Chasma, which is part of the Valles Marineris. These layers were initially deposited within Candor, and have subsequently been eroded by a variety of processes, including wind and downslope motion due to gravity. The effect of erosion is manifest differently in the different layers and at different locations within the layered material. For example, the upper portion of the Candor deposit seen in the lower one-third of the image appears more intact, whereas downslope there is pronounced fluting to create produced "spur and gully" slopes. Relatively dark materials are seen throughout the image and appear to mantle select areas of the layered deposits. When seen in other areas by THEMIS, and at higher resolution by the Mars Global Surveyor camera, these dark materials often form sand dunes. The dark mantling material in Candor is likely dark sand as well. Several particularly dark patches can be seen near the left (western) edge of the image, approximately one quarter of the way up from the bottom of the image. Very few impact craters of any size can be seen in this image, indicating that the erosion and transport of material is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded. The Story The smooth, triangular shape near the center of this image is the plateau of a canyon, with walls that dramatically descend on either side. This canyon is named Chasma, which means "blaze" or "white" in Latin. The lighter, brighter material of the southern canyon wall displays erosional streaks that almost do happen to look like a white blaze. Toward the bottom left of the image, you can see how the relatively brighter material from the top has been carried down to the bottom. Notice that the upper, grayer part of the southern canyon walls don't seem to have the same erosional flutes as the brighter material just below it. By looking at such differences on the same canyon wall, geologists can begin to understand the kinds of materials that make up each layer of the canyon wall, and how resistant each is to erosion. No matter what part of the canyon you look at, erosion has created the beautiful sequence of layered rocks within Candor. Sometimes it's the wind that acts, and sometimes gravity, which pulls material from the upper parts of the canyon downslope. Be sure to click on the above image for a close-up view of all of the subtle layers and ripples. Look also for some dark, almost black patches (bottom left, about a quarter of the way up). These dark splotches are most likely made of sand. In fact, much of the darker areas seen in this image are probably made of sand. The sand often forms in dunes, as both THEMIS and the higher resolution camera on Mars Global Surveyor, Odyssey's sister orbiter, have shown. With all of the wind and downslope erosion,, , this area is fairly active geologically. You can tell because there are very few impact craters of any size to be seen. That means material is being transported at a rate that's rapid enough to bury or erode any craters that do form. Candor Chasma is part of Valles Marineris, the large canyon system that slices across a large part of the red planet. If Valles Marineris were located on Earth, it would stretch all the way from the west coast to the east coast of the United States. |
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