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Images of Goddard Space Flight Center (GSFC) and Jet Propulsion Laboratory (JPL) and Jet Propulsion Laboratory
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Iapetus Thermal Radiation Im
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| Description |
Iapetus Thermal Radiation Image |
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This image of the infrared heat radiation from Saturn's moon Iapetus was obtained by the Cassini composite infrared spectrometer instrument 16 hours before Cassini's closest approach to this mysterious moon, on December 31, 2004. The thermal radiation is shown as both a grayscale image, equivalent to what we would see if our eyes were sensitive to infrared wavelengths near 15 microns, and as a color-coded temperature map. A previously-released mosaic obtained by Cassini's imaging camera shortly before the composite infrared spectrometer observation, with similar scale and orientation, is also shown for comparison. Temperatures reach nearly 130 Kelvin (-226 Fahrenheit) at noon on the equator on the dark material that covers most of this side of Iapetus, making high noon on Iapetus's dark side probably the warmest places in the Saturn system. This is much warmer than temperatures on another Saturnian moon, Phoebe, measured by composite infrared spectrometer in June 2004. Those Phoebe temperature measurements peaked near 112 Kelvin (-258 Fahrenheit), because though Phoebe is almost as dark as Iapetus's dark material and absorbs nearly as much sunlight, Phoebe rotates much more quickly (once every 9 hours, compared to 79 days for Iapetus). That means the surface has less time to heat up during the day. Temperatures on Iapetus's bright material are much colder, peaking near 100 Kelvin (-280 Fahrenheit), both because the bright material absorbs less sunlight and because it is further from the equator on this side of Iapetus. Temperatures in the large crater near the center of the disc are slightly different from those in surrounding areas, because sloping surfaces within the crater are warmer where they are tilted towards the Sun and cooler when tilted away from the Sun. 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 composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov/. *Credit*: NASA/JPL/GSFC |
| Date |
January 10, 2005 |
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Iapetus Surface Composition
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Iapetus Surface Composition |
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The Cassini visual and infrared mapping spectrometer analyzed the surface composition of Saturn's moon Iapetus as Cassini flew over the polar region on Dec. 31, 2004. The image at left shows the reflectance at 4-microns, which is dominated by the minerals on Iapetus' surface. Two large craters are seen in this image. The polar water ice is relatively dark at this wavelength, so the ice cap is not seen. The next frame shows carbon dioxide on the surface. The carbon dioxide peaks at mid latitudes and shows less strength at the pole and along the equator (the dark band curving near the left edge of the image). The third frame shows the strength of water absorption on Iapetus. The brightest regions are due to water ice near the pole. The grayer areas indicate water bound to minerals on the surface. The color composite shows water as blue, carbon dioxide as green, and non-ice minerals as red. 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 visible and infrared mapping spectrometer team is based at the University of Arizona, Tucson. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov. For more information about the visual and infrared mapping spectrometer visit http://wwwvims.lpl.arizona.edu/. *Credit*: NASA/JPL/GSFC |
| Date |
January 10, 2005 |
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The Hole at the Pole
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The Hole at the Pole |
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The Cassini data presented in this view appear to confirm a region of warm atmospheric descent into the eye of a hurricane-like storm locked to Saturn's south pole. The view shows temperature data from the Cassini spacecraft composite infrared spectrometer overlaid onto an image from the imaging science subsystem wide-angle camera. The composite infrared spectrometer data refer to a depth in Saturn's upper stratosphere where the pressure is 0.5 millibars (324 kilometers above the 1-bar level), a region higher than that imaged by the imaging camera and visual and infrared spectrometer during the same observation period. The composite infrared spectrometer data show a very small hot spot over the pole, similar in size to the "eye" of the storm seen in the imaging science subsystem images. See also Looking Saturn in the Eye and Saturn's Surprisingly Stormy South for related images. The color scale at the bottom indicates the temperature in Kelvin corresponding to the colors of the temperature map. Numbers on the grid correspond to lines of latitude and longitude on the planet. Infrared images taken through the Keck I telescope by ground-based observers had previously shown the south polar spot to be warm. Cassini's composite infrared spectrometer has confirmed this with higher resolution temperature maps of the area (like the map displayed here) and sees a temperature increase of about 2 Kelvin (4 degrees Fahrenheit) at the pole. The temperatures are in the stratosphere and higher up than the clouds seen by the Cassini imaging and visual and infrared mapping spectrometer instruments, but they suggest that the atmosphere sinks over the south pole. Because the pressure increases with depth, the descending atmosphere compresses and heats up. The warmer temperatures over the south pole also indicate that the vortex winds are decaying with height in the stratosphere. The descent implied by the temperatures nicely supports the lower cloud altitudes observed by the imaging camera and visual and infrared spectrometer instruments at the pole. The image and atmospheric data were acquired on Oct. 11, 2006, when Cassini was approximately 340,000 kilometers (210,000 miles) from Saturn. The wide-angle camera image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 752 nanometers. The image has been contrast enhanced using digital image processing techniques. The unprocessed image shows an oblique view toward the pole, and was reprojected to show the planet from a perspective directly over the south pole. Scale in the original image was about 17 kilometers (11 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. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . The composite infrared spectrometer team homepage is at http://cirs.gsfc.nasa.gov/ . *Credit:* NASA/JPL/Space Science Institute/GSFC |
| Date |
November 9, 2006 |
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Iapetus Temperature Variatio
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Iapetus Temperature Variation Map |
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This plot shows how daytime temperatures at low latitudes on the dark material on Saturn's moon Iapetus vary with time of day, from about 130 Kelvin (-226 Fahrenheit) at noon to about 70 Kelvin (-334 Fahrenheit) at sunset. The observations are compared to a "forecast" model (green line) which predicts temperatures based on an assumed value of a parameter called the "thermal inertia. This measures how well the surface can retain heat as conditions change. Rock or solid ice has a high thermal inertia, roughly 2,000,000 as measured in the obscure units used for thermal inertia, meaning that it is good at storing heat and cools down or heats up relatively slowly. On Iapetus, in contrast, temperatures drop precipitously in the afternoon as the Sun sinks towards the horizon, and a very small value of the thermal inertia (30,000 units) is needed in the model to match the data. This means that Iapetus's surface is extremely bad at storing heat, and is thus extremely fluffy, probably due to the pulverizing effect of billions of years of meteorite impacts, though the mysterious process that has darkened this side of Iapetus may also have played a role. 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 composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov/. *Credit*: NASA/JPL/GSFC |
| Date |
January 10, 2005 |
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Enceladus Keeps the Home Fir
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| Description |
Enceladus Keeps the Home Fires Burning |
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On Nov. 9, 2006, Cassini's composite infrared spectrometer captured its first view of the infrared heat radiation emanating from the "tiger stripe" fractures at the south pole of Saturn's moon Enceladus (right) since the discovery of the hot spot 16 months earlier (left). The original discovery was made just before a close flyby of Enceladus on July 14, 2005, and coincided with the discovery of plumes of water-rich gas and ice particles jetting out of the tiger stripes. However, the spacecraft's orbit did not provide any good views of the south pole for follow-up observations until November 2006. The new observations were made from a range of 110,000 kilometers (68,350 miles), slightly more distant than the 80,000-kilometer range (49,700 miles) of the original observations. Comparison of the two images shows that the south polar region continues to be active, and the distribution of temperatures there has changed little in 16 months. The distribution of heat radiation suggests that most or all of the south polar heat comes from the tiger stripes themselves, though the individual stripes are not resolved at the approximate 30-kilometer (19-mile) spatial resolution of these images. The images show the intensity of heat radiation in the 10- to 16-micron wavelength range, translated into temperature and displayed in false color. Peak south polar temperature on both dates reached about 85 Kelvin (minus 306 degrees Fahrenheit), averaged over the 30-kilometer (19-mile) spatial resolution of the data. However, the variation in brightness with wavelength, which is also measured by the composite infrared spectrometer, reveals that the warm region includes small areas, possibly zones a few 100 meters (320 feet) wide along the length of the tiger stripes, that are at higher temperatures, reaching at least 130 Kelvin (minus 225 degrees Fahrenheit) and perhaps much warmer still. While the south polar tiger stripes are almost certainly heated by energy from the moon's interior, daytime regions at low latitudes are warmed by sunlight to temperatures in the high 70s Kelvin (about minus 320 degrees Fahrenheit). The white numbers on the images show west longitudes on Enceladus, which is 500 kilometers (310 miles) in diameter. The dashed line shows the terminator, the boundary between day and night. The blotchy appearance of the cooler regions away from the south pole, and of the sky beyond the globe of Enceladus, is an artifact resulting from the fact that apart from the polar hot spot, the composite infrared spectrometer can barely detect the very faint heat radiation from this very cold moon. 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 was designed, developed and assembled at JPL. The, composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The composite infrared spectrometer team homepage is http://cirs.gsfc.nasa.gov/. *Image Credit:* NASA/JPL/GSFC/Southwest Research Institute |
| Date |
December 22, 2006 |
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Titan Sea and Lake Superior
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Titan Sea and Lake Superior |
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This side-by-side image shows a Cassini radar image (on the left) of what is the largest body of liquid ever found on Titan's north pole, compared to Lake Superior (on the right). This close-up is part of a larger image (see Titan (T25) Viewed by Cassini's Radar - Feb. 22, 2007) and offers strong evidence for seas on Titan. These seas are most likely liquid methane and ethane. This feature on Titan is at least 100,000 square kilometers (39,000 square miles), which is greater in extent than Lake Superior (82,000 square kilometers or 32,000 square miles), which is one of Earth's largest lakes. The feature covers a greater fraction of Titan than the largest terrestrial inland sea, the Black Sea. The Black Sea covers 0.085 percent of the surface of the Earth, this newly observed body on Titan covers at least 0.12 percent of the surface of Titan. Because of its size, scientists are calling it a sea. The image on the right is from the SeaWiFS project, NASA's Goddard Space Flight Center, Greenbelt, Md. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL/GSFC |
| Date |
March 13, 2007 |
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Warm and Dry on Iapetus
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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 composite infrared spectrometer team homepage is http://cirs.gsfc.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/GSFC/SwRI/SSI, This image compares midday temperatures on Saturn's moon Iapetus, recorded by the composite infrared spectrometer instrument during Cassini's close Sept. 10, 2007 flyby, with images of the same region recorded during the same flyby by the Cassini imaging science subsystem, shown on the right. See The Other Side of Iapetus for full imaging mosaic. Smallest features visible in the composite infrared spectrometer image (on the left) are about 8 kilometers (5 miles) across. The red rectangle on the visible light (right) image shows the region covered by infrared spectrometer, which extends a distance of 385 kilometers (240 miles) from 36 north, 212 west to 22 south, 220 west. The composite infrared spectrometer determined surface temperatures by measuring the spectrum of infrared radiation emitted by Iapetus in the 9 to 16 micron wavelength range. The dark regions are warmer because they absorb more of the sunlight shining on Iapetus, so dark spots in the visible (right) image show up as warm spots in the infrared image on the left. Temperatures near the equator vary between about 128 Kelvin (minus 229 degrees Fahrenheit) in the darkest regions and about 113 Kelvin (minus 256 degrees Fahrenheit) in the brightest regions. This relatively small temperature difference has a large effect on Iapetus, because at the temperature of the dark regions, a large amount of water ice, which is abundant on most moon surfaces in the Saturn system, can be lost by evaporation over the several-billion year age of Iapetus' surface. Composite infrared spectrometer scientists calculate that when daytime temperatures reach 128 Kelvin (minus 229 degrees Fahrenheit), about 20 meters (65 feet) of ice can be lost per billion years. In the bright regions, with peak temperatures of 113 Kelvin (minus 256 degrees Fahrenheit), only about 10 centimeters, or 2.5 inches, of ice is lost in the same period. It is thus likely that the ice has evaporated completely from the surface of the dark regions of Iapetus, darkening them further, and has collected in the neighboring bright regions, making them brighter, thereby exaggerating initially modest brightness variations. This process is known as thermal segregation. Models by the composite infrared spectrometer team also show that ice evaporated from the warm dark terrain at low latitudes can collect at higher latitudes, and can thus explain the bright polar caps on the dark leading side of Iapetus as well as the relatively dark equatorial regions on the bright trailing side. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. |
| Date |
October 8, 2007 |
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High Above Saturn's Cloud To
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Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
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These graphs illustrate wind strength (bottom) and temperature above Saturn. The data were acquired by the Cassini spacecraft's composite infrared spectrometer when Saturn had just begun summer in its southern hemisphere. Altitude increases in the upward direction, and Saturn's south pole is to the right. The color red indicates higher temperatures, and stronger winds. As the top graph show, temperatures are cooler in the troposphere (the layer just above the cloud deck). In the upper stratosphere (the layer above the troposphere), temperatures increase toward the south pole. Temperature variation is muted in the upper troposphere. These observed temperature changes allow the east-west winds to be determined. The measured cloud-top winds from NASA's Voyager mission have also been used to create this wind plot. This is the first time that the stratospheric winds have been determined. They show a marked decline of about 140 meters per second (approximately 300 miles per hour) at low latitudes, moving from the cloud tops to higher levels. The origin of this decay, or wind speed reduction, is not known. Temperature maps obtained in the future from Cassini's new position in orbit around Saturn will have higher latitude resolution, and are expected to show more detail, helping us to unravel the riddles of Saturn's winds above the cloud tops. 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 composite infrared spectrometer team is located at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://cirs.gsfc.nasa.gov/ . Image Credit: NASA/JPL/GSFC |
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Saturn's Rings, Cold and Col
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Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
The varying temperatures of Saturn's rings are depicted here in this false-color image from the Cassini spacecraft. This image represents the most detailed look to date at the temperature of Saturn's rings. The image was made from data taken by Cassini's composite infrared spectrometer instrument. Red represents temperatures of about 110 Kelvin (-261 degrees Fahrenheit), and blue 70 Kelvin (-333 degrees Fahrenheit). Green is equivalent to 90 Kelvin (-298 degrees Fahrenheit). Water freezes at 273 Kelvin (32 degrees Fahrenheit). The spatial resolution of the ring portion of the image is 200 kilometers (124 miles). The data show that the opaque region of the rings, like the outer A ring (on the far right) and the middle B ring, are cooler, while more transparent sections, like the Cassini Division (in red just inside the A ring) or the inner C ring (shown in yellow and red), are relatively warmer. The temperature data were taken on July 1, 2004, of the unlit side of the rings. In order to show the full breadth of the rings, a strip of temperature data was mapped onto a picture of the lit side of the rings taken with the Cassini narrow angle camera on May 11, 2004, a little over a month before Saturn orbit insertion. Cassini is too close to the planet and hence no pictures of the unlit side of the rings are available, so the temperature data were mapped onto a picture of the lit side of rings. Saturn is overexposed and pure white in this picture. Saturn's moon Enceladus is visible below the rings, toward the center. The original picture and caption are available at http://photojournal.jpl.nasa.gov/catalog/PIA05410. 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 Science and Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The Composite Infrared Spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov . Image Credit: NASA/JPL/GSFC/Ames |
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Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
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Auroral "Footprints" of Jupiter's Moons February 27, 2002 A drawing illustrates how flows of electrons steered by Jupiter's magnetic field connect three of Jupiter's large moons with the upper atmosphere near Jupiter's north and south poles. The currents stimulate ultraviolet aurora glows in Jupiter's upper atmosphere. Observations with NASA's Hubble Space Telescope, coordinated with the late 2000 flyby of Jupiter by NASA's Cassini spacecraft, captured those auroral footprints for the moons Io (left), Europa (right) and Ganymede (center). In the illustration, Jupiter's magnetic field lines are presented in blue, the moons' orbital paths around Jupiter in yellow. Pink loops from each of the moons to Jupiter's poles depict the flux tubes that are the paths of powerful electric currents. The Space Telescope Science Institute, Baltimore, Md., manages space operations for Hubble 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 the Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. Cassini 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 mission for NASA's Office of Space Science. Credit: NASA/John Spencer, Lowell Observatory and John Clarke, Boston University More information about the Cassini and Galileo joint observations of the Jupiter system is available online at: http://www.jpl.nasa.gov/jupiterflyby. Cassini 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 Galileo and Cassini missions for NASA's Office of Space Science, Washington, D.C. |
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Saturn's Rings, Cold and Col
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| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
The varying temperatures of Saturn's rings are depicted here in this false-color image from the Cassini spacecraft. This image represents the most detailed look to date at the temperature of Saturn's rings. The image was made from data taken by Cassini's composite infrared spectrometer instrument. Red represents temperatures of about 110 Kelvin (-261 degrees Fahrenheit), and blue 70 Kelvin (-333 degrees Fahrenheit). Green is equivalent to 90 Kelvin (-298 degrees Fahrenheit). Water freezes at 273 Kelvin (32 degrees Fahrenheit). The spatial resolution of the ring portion of the image is 200 kilometers (124 miles). The data show that the opaque region of the rings, like the outer A ring (on the far right) and the middle B ring, are cooler, while more transparent sections, like the Cassini Division (in red just inside the A ring) or the inner C ring (shown in yellow and red), are relatively warmer. The temperature data were taken on July 1, 2004, of the unlit side of the rings. In order to show the full breadth of the rings, a strip of temperature data was mapped onto a picture of the lit side of the rings taken with the Cassini narrow angle camera on May 11, 2004, a little over a month before Saturn orbit insertion. Cassini is too close to the planet and hence no pictures of the unlit side of the rings are available, so the temperature data were mapped onto a picture of the lit side of rings. Saturn is overexposed and pure white in this picture. Saturn's moon Enceladus is visible below the rings, toward the center. The original picture and caption are available at http://photojournal.jpl.nasa.gov/catalog/PIA05410. 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 Science and Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The Composite Infrared Spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov . Image Credit: NASA/JPL/GSFC/Ames |
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Warm Fractures on Enceladus
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Warm Fractures on Enceladus |
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This image shows the warmest places in the south polar region of Saturn's moon Enceladus. The unexpected temperatures were discovered by Cassini's composite infrared spectrometer during a close flyby on July 14, 2005. The image shows how these temperatures correspond to the prominent, bluish fractures dubbed "tiger stripes," first imaged by Cassini's imaging science subsystem cameras. Working together the two teams were able to pinpoint the exact location of the warmest regions on Enceladus. The composite infrared spectrometer instrument measured the infrared heat radiation from the surface at wavelengths between 9 and 16.5 microns within each of the 10 squares shown here. Each square is 6 kilometers (4 miles) across. The color of each square, and the number shown above it, describe the composite infrared spectrometer's measurement of the approximate average temperature of the surface within that square. The warmest temperature squares, at 91 and 89 degrees Kelvin (minus 296 and minus 299 degrees Fahrenheit), are located over one of the "tiger stripe" fractures. They contrast sharply with the surrounding temperatures, which are in the range 74 to 81 degrees Kelvin (minus 326 to minus 313 degrees Fahrenheit). The detailed composite infrared spectrometer data suggest that small areas near the fracture are at substantially higher temperatures, well over 100 degrees Kelvin (minus 279 degrees Fahrenheit). Such "warm" temperatures are unlikely to be due to heating of the surface by the feeble sunlight striking Enceladus' south pole. They are a strong indication that internal heat is leaking out of Enceladus and warming the surface along these fractures. Evaporation of this relatively warm ice probably generates the cloud of water vapor detected above Enceladus' south pole by several other Cassini instruments. Scientists are unsure how the internal heat reaches the surface. The process might involve liquid water, slushy brine, or soft but solid ice. The imaging science subsystem image is an enhanced color view with a pixel scale of 122 meters (400 feet) that was acquired at the same time as the composite infrared spectrometer data. It covers a region 125 kilometers (75 miles) across. The spacecraft's distance from Enceladus was 21,000 kilometers (13,000 miles). The broad bluer fractures that can be seen running from the upper left to the lower right of the image are 1 to 2 kilometers (0.6 to 1.2 miles) wide and more than 100 kilometers (60 miles) long. The fractures are thought to be bluer than the surrounding surface because coarser-grained ice (which has a blue color just as thick masses of ice, like glaciers and icebergs, do on Earth) has been exposed in the fractures. The color image was constructed using an ultraviolet filter (centered at 338 nanometers) in the blue channel, a clear filter in the green channel, and an infrared filter (centered at 930 nanometers) in the red channel. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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 composite infrared spectrometer team homepage is http://cirs.gsfc.nasa.gov/ . The imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/GSFC/Space Science Institute |
| Date |
July 29, 2005 |
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Enceladus Temperature Map
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Enceladus Temperature Map |
| Full Description |
This image shows the surprise that startled Cassini scientists on the composite infrared spectrometer team when they got their first look at the infrared (heat) radiation from the south pole of Saturn's moon Enceladus. There is a dramatic warm spot centered on the pole that is probably a sign of internal heat leaking out of the icy moon. The data were taken during the spacecraft's third flyby of this intriguing moon on July 14, 2005. Based on data from previous flybys, which did not show the south pole well, team members expected that the south pole would be very cold, as shown in the left panel. Enceladus is one of the coldest places in the Saturn system because its extremely bright surface reflects 80 percent of the sunlight that hits it, so only 20 percent is available to heat the surface. As on Earth, the poles should be even colder than the equator because the sun shines at such an oblique angle there. The right hand panel shows a global temperature image made from measurements of Enceladus' heat radiation at wavelengths between 9 and 16.5 microns. Cassini made the observation from a distance of 84,000 kilometers (52,000 miles) on the approach to Enceladus, and the image shows details as small as 25 kilometers (16 miles). Equatorial temperatures are much as expected, topping out at about 80 degrees Kelvin (-315 degrees Fahrenheit), but the south pole is occupied by a well-defined warm region reaching 85 Kelvin (-305 degrees Fahrenheit). That is 15 degrees Kelvin (27 degrees Fahrenheit) warmer than expected. The composite infrared spectrometer data further suggest that small areas of the pole are at even higher temperatures, well over 110 degrees Kelvin (-261 degrees Fahrenheit). Evaporation of this relatively warm ice probably generates the cloud of water vapor detected above Enceladus' south pole by several other Cassini instruments. The south polar temperatures are very difficult to explain if sunlight is the only energy source heating the surface, though exotic sunlight-trapping mechanisms have not yet been completely ruled out. It therefore seems likely that portions of the polar region are warmed by heat escaping from the interior of the moon. This would make Enceladus only the third solid body in the solar system, after Earth and Jupiter's volcanic moon Io, where hot spots powered by internal heat have been detected. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The composite infrared spectrometer team homepage is, http://cirs.gsfc.nasa.gov/ . Credit: NASA/JPL/GSFC |
| Date |
July 29, 2005 |
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Phoebe's Radiation
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Phoebe's Radiation |
| Full Description |
This image shows thermal radiation from the day and night sides of Saturn's moon Phoebe, taken by the composite infrared spectrometer onboard Cassini 1.8 hours before the spacecraft's closest approach to Phoebe on June 11, 2004. The left-hand panel displays the image in grayscale format, showing the brightness of Phoebe's radiation in the wavelength range 15-17 microns, which is about 25 times the longest wavelength visible to the naked eye. In the middle panel this brightness is used to estimate the surface temperature distribution across Phoebe. Temperatures are given in degrees Kelvin, and vary from a relatively toasty 107 Kelvin (-267 Fahrenheit), in the late morning near the equator (white, lower right), to less than 75 Kelvin (-324 Fahrenheit) in the northern hemisphere in the pre-dawn hours (dark blue, upper left). The "ragged edge" of Phoebe in this region is an instrumental artifact. Temperatures are affected strongly by topography, as can be seen by comparison with the visible-wavelength image (right). Some of the coldest temperatures are found in the shadowed region inside the large depression in the northern hemisphere (upper right). 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 and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini composite infrared spectrometer home page at http://cirs.gsfc.nasa.gov/ . Image Credit: NASA/JPL/Goddard Space Flight Center |
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Atlas Found!
| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
The Cassini spacecraft has sighted the tiny moon Atlas, which is seen here for the first time since Voyager 1 flew past Saturn in 1980. Cassini's narrow angle camera captured a sequence of 112 images in visible light, which were used to create a movie of Atlas and other moons racing around the outer edge of Saturn's rings. One of those images is shown here. Over the course of almost five and one-quarter hours, Cassini watched the moons as they circled the planet, snapping 1.2-second exposures about 12 minutes apart. These images were part of a sequence designed specifically to search for small moons near Saturn's F ring. Contrast was enhanced in the images, and the rings themselves were overexposed intentionally, to make these small moons visible. A group of three moons can be seen rounding the right loop of Saturn's rings, followed by a fourth moon. In the first group, the moon exterior to Saturn's thin, knotted F ring is Epimetheus (116 kilometers, 72 miles across), the two moons interior to the F ring are Prometheus (102 kilometers, 63 miles across) and tiny unresolved Atlas (32 kilometers, 20 miles across). The fourth moon seen here, exterior to the F ring and tagging along behind the others, is Pandora (84 kilometers, 52 miles across). At the same time, on the left side, Janus can be seen (181 kilometers, 113 miles across). The view is taken looking upward from Cassini's southern vantage point beneath the ring plane. The moons visible here are orbiting Saturn in a plane that is tilted 67 degrees away from the viewer. These images were taken on May 26 and 27, 2004, from a distance of approximately 19.2 million kilometers (11.9 million miles) from Saturn. The image scale is approximately 114 kilometers (71 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 Cassini-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org . Image Credit: NASA/JPL/Goddard Space Flight Center |
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Phoebe Temperature Maps
| Description |
Phoebe Temperature Maps |
| Full Description |
A montage of maps of Saturn's moon Phoebe shows surface temperatures at various times of day as determined by the composite infrared spectrometer onboard Cassini during the June 11, 2004, Phoebe flyby. The asterisk on each map shows the location of the subsolar point, where the Sun is directly overhead. This point moves across the surface as Phoebe rotates. It is morning in regions to the left of the subsolar point, and afternoon in regions to the right. Like a newspaper weather map, different colors indicate different temperatures, though Phoebe's temperatures are distinctly cooler than even the coldest January day on Earth. Equatorial temperatures peak in the early afternoon near 112 Kelvin (-257 Fahrenheit), plunging to 78 Kelvin (-319 Fahrenheit) before dawn, and are even colder at higher latitudes. The large day/night temperature contrasts imply that Phoebe's surface is covered in loose dust or ice particles that store little heat and thus cool off rapidly at night. Regions of Phoebe's surface that were not observed are shown in black. Most of the maps show the effect on surface temperatures of the large crater-like depression seen in Cassini's visible-wavelength images of Phoebe, which is located just left of center in these maps. Crater walls that are shadowed and cold in the early morning in the first map are sunlit and warm in the late afternoon in the final map. 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 composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini composite infrared spectrometer home page at http://cirs.gsfc.nasa.gov/ . Image Credit: NASA/JPL/Goddard Space Flight Center |
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Slower Spinning Rings #1
| Description |
Slower Spinning Rings #1 |
| Full Description |
The Cassini composite infrared spectrometer obtained temperature maps of Saturn's main rings (A, B and C) that showed ring temperatures decreasing with increasing solar phase angle (the change of the sun-spacecraft-ring angle) on both the lit and unlit sides of the rings. Temperature changes throughout Saturn's main rings, as measured by the instrument, indicate that Saturn ring particles spin slowly compared to their orbital periods of 6 to 14 hours. They may spin several times per orbit to less than one time per orbit. Scans are shown for the lit and unlit rings, at relatively low (less than 60-degree) and high (more than 130-degree) phase angles. Each scan was painted on the rings at the correct ring orientation, creating a false color image. Warmer temperatures about minus 262 degrees Fahrenheit (110 Kelvin) are shown in red and cooler temperatures about minus 343 degrees (65 K) are shown in blue. Other colors indicate temperatures between minus 343 degrees and minus 262 degrees (65 K and 110 K). The scans of the lit rings are shown in the two panels on the left and scans of the unlit rings are shown in the two panels on the right. The thermal characteristics of each main ring vary noticeably with phase angle. Radial scans of the A, B and C rings show a decrease in temperature with increasing phase angle for both the lit and unlit sides of the rings. The C ring and Cassini Division exhibit the largest change in temperature. The temperature of the lit C ring decreases by about 22 degrees (12 Kelvin) between low and high phase angles. A similar contrast is present for the unlit side of the C ring. The C ring and Cassini Division are darker than the A and B rings so they can absorb more heat from the Sun. The lit B ring shows a temperature contrast of approximately 18 degrees (10 K) while the unlit B ring shows very little thermal contrast. Very little sunlight may make it through the thick B ring to its unlit side. The lit A ring is particularly interesting because the magnitude of the thermal contrast decreases with increasing radial distance from Saturn. The outer A ring shows only a small temperature change with phase angle, possibly because it contains smaller, or more rapidly rotating ring particles, which would have more uniform temperatures with phase angle. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov/. Credit: NASA/JPL/GSFC |
| Date |
September 5, 2005 |
|
Slower Spinning Rings #2
| Description |
Slower Spinning Rings #2 |
| Full Description |
Temperature changes mapped with Cassini's composite and infrared spectrometer throughout Saturn's main rings show the ring temperatures decreasing with the increase of the Sun-spacecraft-ring angle (called phase angle) on both the lit and unlit sides of the rings. These temperature changes indicate that the ring particles spin slowly compared to their orbital periods of 6 to 14 hours. They may spin several times per orbit to less than one time per orbit. Four scans are shown for the lit and unlit rings, at relatively low (less than 60 degrees) and high (more than 130 degrees) phase angles. Warmer temperatures about minus 262 degrees Fahrenheit (110 Kelvin) are shown in red and cooler temperatures about minus 343 degrees (65 K) are shown in blue. Other colors indicate temperatures between minus 343 degrees and minus 262 degrees (65 K and 110 K). The top two scans are for the lit rings and the bottom two scans are for the unlit rings. The change in ring temperature between each scan can be seen clearly. The thermal characteristics of each main ring vary noticeably with phase angle. Radial scans of the A, B and C rings show a decrease in temperature with increasing phase angle for both the lit and unlit sides of the rings. The C ring and Cassini Division exhibit the largest change in temperature. The temperature of the lit C ring decreases by about 22 degrees (12 Kelvin) between low and high phase angles. A similar contrast is present for the unlit side of the C ring. The C ring and Cassini Division are darker than the A and B rings so they can absorb more heat from the Sun. The lit B ring shows a temperature contrast of approximately 18 degrees (10 K) while the unlit B ring shows very little thermal contrast. Very little sunlight may make it through the thick B ring to its unlit side. The lit A ring is particularly interesting because the magnitude of the thermal contrast decreases with increasing radial distance from Saturn. The outer A ring shows only a small temperature change with phase angle, possibly because it contains smaller, or more rapidly rotating ring particles, which would have more uniform temperatures with phase angle. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov/. |
| Date |
September 5, 2005 |
|
Iapetus Temperature Map
| Description |
Iapetus Temperature Map |
| Full Description |
This temperature map of Saturn's moon Iapetus is constructed from observations of Iapetus's infrared heat radiation taken with the Cassini composite infrared spectrometer instrument during the Dec. 31, 2004 flyby. The orange asterisk marks the point on Iapetus where the Sun is directly overhead. Temperatures reach nearly 130 Kelvin (-226 Fahrenheit) at noon on the equator on the dark material that covers most of this side of Iapetus, making high noon on Iapetus's dark side probably the warmest places in the Saturn system. This is much warmer than temperatures on the moon Phoebe measured by the composite infrared spectrometer in June 2004, which peaked near 112 Kelvin (-258 Fahrenheit). That's because, although Phoebe is almost as dark as Iapetus's dark material and absorbs nearly as much sunlight, Phoebe rotates much more quickly (once every 9 hours, compared to 79 days for Iapetus). That means the surface has less time to heat up during the day. Temperatures on Iapetus' bright material are much colder, peaking near 100 Kelvin (-280 Fahrenheit), both because the bright material absorbs less sunlight and because it is further from the equator on this side of Iapetus. 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 composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the instrument team's home page, http://cirs.gsfc.nasa.gov/. *Credit*: NASA/JPL/GSFC |
| Date |
January 10, 2005 |
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Searching for Warmth
| Description |
The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures. |
| Full Description |
The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures. This view shows excess heat radiation from cracks near the moon's south pole. These warm fissures are the source of plumes of dust and gas seen by multiple instruments on the Cassini spacecraft during its flyby of Enceladus on July 14, 2005, as described in a series of papers in the March 10, 2006, issue of the journal Science. This image shows two arrays of temperature readings across the surface of Enceladus, as measured by the Cassini composite infrared spectrometer, superimposed on images of the surface taken simultaneously by the imaging science subsystem. Surface temperatures in Kelvin, derived from the intensity of infrared radiation detected by the composite infrared spectrometer, are shown along with their formal uncertainties, although true uncertainties for temperatures below about 75 Kelvin (minus 325 degrees Fahrenheit) are not easily described by a single number. Enhanced thermal emission is seen in the vicinity of the prominent "tiger stripe" fissures discovered by the imaging cameras. In this image, the excess emission is most strongly seen in the left-most composite infrared spectrometer field of view, which includes a fissure near the end of one of the tiger stripes. The peak temperatures, 86 Kelvin and 90 Kelvin (minus 305 and minus 298 degrees Fahrenheit) respectively, are averages over the composite infrared spectrometer field of view, and other composite infrared spectrometer data suggest that much higher temperatures, up to at least 145 Kelvin (minus 199 degrees Fahrenheit), occur in narrow zones a few hundred meters wide along the tiger stripe fissures. See (PIA07794) for a related image. This image is centered near longitude 135 west, latitude 65 south, and each square from the composite infrared spectrometer field of view is 17.5 kilometers (10.9 miles) across. This Cassini narrow-angle camera image has been cropped and resized for presentation. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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 composite infrared spectrometer team homepage is http://cirs.gsfc.nasa.gov/. The imaging team homepage is at http://ciclops.org *Credit:* NASA/JPL/GSFC/Space Science Institute |
| Date |
March 9, 2006 |
|
Searching for Warmth
| Description |
The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures. |
| Full Description |
The exciting mystery of an active south polar region on Saturn's icy moon Enceladus continues to unfold as scientists make the correlation between geologically youthful surface fractures and unusually warm temperatures. This view shows excess heat radiation from cracks near the moon's south pole. These warm fissures are the source of plumes of dust and gas seen by multiple instruments on the Cassini spacecraft during its flyby of Enceladus on July 14, 2005, as described in a series of papers in the March 10, 2006, issue of the journal Science. This image shows two arrays of temperature readings across the surface of Enceladus, as measured by the Cassini composite infrared spectrometer, superimposed on images of the surface taken simultaneously by the imaging science subsystem. Surface temperatures in Kelvin, derived from the intensity of infrared radiation detected by composite infrared spectrometer, are shown along with their formal uncertainties, although true uncertainties for temperatures below about 75 Kelvin (minus 325 degrees Fahrenheit) are not easily described by a single number. Enhanced thermal emission is seen in the vicinity of the prominent "tiger stripe" fissures discovered by the imaging cameras. In this image, the excess emission is near the center of the composite infrared spectrometer array, directly over a tiger stripe fissure. The peak temperatures, 86 Kelvin and 90 Kelvin (minus 305 and minus 298 degrees Fahrenheit) respectively, are averages over the composite infrared spectrometer field of view, and other composite and infrared spectrometer data suggest that much higher temperatures, up to at least 145 Kelvin (minus 199 degrees Fahrenheit), occur in narrow zones a few hundred meters wide along the tiger stripe fissures. See (PIA07793) for a related image. This image was taken nearly three times closer to the moon and is centered near longitude 120 west, latitude 82 south, and each composite infrared spectrometer field of view is 6.0 kilometers (3.7 miles) across. This Cassini narrow-angle camera image was cropped and resized for presentation. 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 was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. 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 composite infrared spectrometer team homepage is http://cirs.gsfc.nasa.gov/. The imaging team homepage is at http://ciclops.org *Credit:* NASA/JPL/GSFC/Space Science Institute |
| Date |
March 9, 2006 |
|
Hot Shot
| title |
Hot Shot |
| description |
The black dot in this picture of the Sun is Mercury. The planet made a rare pass in front of the Sun on May 7, 2003. The SOHO and TRACE spacecraft were watching with all instruments. The spacecraft websites are among many with Mercury transit galleries. *Image Credit*: NASA Goddard Space Flight Center |
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Home Reef Reborn
| title |
Home Reef Reborn |
| description |
In the South Pacific, south of Late Island along the Tofua volcanic arc in Tonga, the volcanic island Home Reef is being re-born. The island is thought to have emerged after a volcanic eruption in mid-August that also spewed large amounts of floating pumice into Tongan waters and swept across to Fiji about 350 km (220 miles) to the west of where the new island formed. In 2004, a similar eruption created an ephemeral island about 0.5 by 1.5 km (0.3 by 0.9 miles) in size, it was no longer visible in an ASTER image acquired November 2005. This simulated natural color image shows the vegetation-covered stratovolcanic island of Late Island in the upper right. Home Reef is found in the lower left. The two bluish plumes are hot seawater that is laden with volcanic ash and chemicals, the larger one can be traced for more than 14 km (8.4 miles) to the east. The image was acquired Oct. 10, 2006 and covers an area of 24.3 by 30.2 km. It is located at 18.9 degrees south latitude, 174.7 degrees west longitude. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitors the changing surface of our planet. It is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Image credit: NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team |
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Dr. Robert Goddard
| title |
Dr. Robert Goddard |
| date |
01.01.1932 |
| description |
The Goddard Space Flight Center was named in honor of Dr. Robert Goddard, a pioneer in rocket development. Dr. Goddard received patents for a multi-stage rocket and liquid propellants in 1914 and published a paper describing how to reach extreme altitudes six years later. That paper, "A Method of Reaching Extreme Altitudes," detailed methods for raising weather-recording instruments higher than what could be achieved by balloons and explained the mathematical theories of rocket propulsion. The paper, which was published by the Smithsonian Institution, also discussed the possibility of a rocket reaching the moon -- a position for which the press ridiculed Goddard. Yet several copies of the report found their way to Europe, and by 1927, the German Rocket Society was established, and the German Army began its rocket program in 1931. Goddard, meanwhile, continued his work. By 1926, he had constructed and tested the first rocket using liquid fuel. Goddard's work largely anticipated in technical detail the later German V-2 missiles, including gyroscopic control, steering by means of vanes in the jet stream of the rocket motor, gimbal-steering, power-driven fuel pumps and other devices. *Image Credit*: NASA |
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Space Pioneer Nancy Roman
| title |
Space Pioneer Nancy Roman |
| date |
01.01.1962 |
| description |
Dr. Nancy Roman, one of the nations top scientists in the space program, is shown with a model of the Orbiting Solar Observatory (OSO). Roman received her PhD in astronomy from the University of Chicago in 1949. In 1959, Dr. Roman joined NASA and in 1960 served as Chief of the Astronomy and Relativity Programs in the Office of Space Science. She was very influential in creating satellites such as the Cosmic Background Explorer (COBE) and the Hubble Space Telescope (HST). She retired from NASA in 1979, but continued working as a contractor at the Goddard Space Flight Center. Throughout her career, Dr. Roman was a spokesperson and advocate of women in the sciences. *Image Credit*: NASA |
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COBE's View of the Milky Way
| title |
COBE's View of the Milky Way |
| date |
01.01.1990 |
| description |
From its orbit around Earth, the Goddard Space Flight Center's Cosmic Background Explorer (COBE) captured this edge-on view of our Milky Way galaxy in infrared light, a form of radiation that humans cannot see but can feel in the form of heat, as part of its mission to test the "Big Bang" theory of the creation of the universe. The theory, first proposed in 1927 by Belgian cosmologist Georges Lematre, holds that the universe began as an incredibly dense "primeval atom" that exploded with tremendous force, unleashing matter and space at the speeds of light. NASA set out to prove the theory with the help of COBE. In addition to proving the Big Bang, the satellite discovered that the cosmic background radiation had indeed been produced in the Big Bang just as scientists originally speculated. The satellite's data even discovered the primordial temperature and density fluctuations that eventually gave rise to the Milky Way and other large-scale objects found in space today. *Image Credit*: NASA |
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Moon Landing Sites
| title |
Moon Landing Sites |
| description |
This image shows the locations of many spacecraft that have landed on the Moon. Green triangles are Apollo missions, yellow are NASA Surveyor missions and red are Russian Luna spacecraft. *Image Credit*: National Space Science Data Center, NASA Goddard Space Flight Center. |
|
First Far Side Photo
| title |
First Far Side Photo |
| date |
10.07.1959 |
| description |
Russia's Luna 3 spacecraft returned the first views ever of the far side of the Moon. The first image was taken at 03:30 UT on 7 October at a distance of 63,500 km after Luna 3 had passed the Moon and looked back at the sunlit far side. The last image was taken 40 minutes later from 66,700 km. A total of 29 photographs were taken, covering 70% of the far side. The photographs were very noisy and of low resolution, but many features could be recognized. This is the first image returned by Luna 3, taken by the wide-angle lens, it showed the far side of the Moon was very different from the near side, most noticeably in its lack of lunar maria (the dark areas). The right three-quarters of the disk are the far side. The dark spot at upper right is Mare Moscoviense, the dark area at lower left is Mare Smythii. The small dark circle at lower right with the white dot in the center is the crater Tsiolkovskiy and its central peak. The Moon is 3475 km in diameter and north is up in this image. A full gallery of Luna 3 photographs can be found at: http://nssdc.gsfc.nasa.gov/imgcat/html/mission_page/EM_Luna_3_page1.html *Image Credit*: NASA National Space Science Data Center |
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Hubble Follows Rapid Changes
…
| Title |
Hubble Follows Rapid Changes in Jupiter's Aurora |
|
North Atlantic Ocean Current
…
| Title |
North Atlantic Ocean Current Velocity |
| Abstract |
Three-dimensional General Circulation Models divide the ocean into a rectangular grid with layered vertical columns. This North Atlantic model uses a 1/6 degree grid with 37 layers. It captured 30 years of velocity, sea-surface temperature, and salinity. The model realistically separates the Gulf Stream from the Florida coast. A feature as small as the Gulf Stream had not appeared in lower-resolution models. |
| Completed |
1999-01-21 |
|
Mars
| Title |
Mars |
| Abstract |
The true global geography of Mars first emerged with comprehensive maps from Mariner 9 and Viking during the 1970's. This visualization tours the Red Planet using the Viking dataset, hitting such features as the Valles Marineris canyons and the Olympus Mons volcano. |
| Completed |
1999-01-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
Zoom into Austin, Texas, usi
…
| Title |
Zoom into Austin, Texas, using Landsat Imagery (WMS) |
| Abstract |
The WMS Global Mosaic dataset was developed at NASA's Jet Propulsion Laboratory (JPL). This global mosaic was produced from visual and near infrared bands taken by the Landsat-7 satellite. Using the panchromatic band to sharpen the final image, a final resolution of 0.5 arc seconds (about 15 meters) can be achieved. This mosaic is available through the Web Mapping Services (WMS) protocol at JPL. This series of images was obtained using a software program called the Digital Earth PC which can use the WMS protocol to obtain images covering an arbitrary region of the earth. These images can be arranged in such a way with the Digital Earth PC software that a nearly continuous zoom effect can be achieved. |
| Completed |
2004-10-21 |
|
A Summer View of Russia's Le
…
| Title |
A Summer View of Russia's Lena Delta and Olenek River |
| Description |
These views of the Russian Arctic were acquired by NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument onĀ July 11, 2004. The brief arctic summer had transformed the frozen tundra and the thousands of lakes, channels, and rivers of the Lena Delta into a fertile wetland, and the usual blanket of thick snow had melted from the vast plains and taiga forests. The images show an area in the northern part of the Sakha Republic in eastern Siberia. The Olenek River wends northeast from the bottom of the images to the upper left, and the delta through which the mighty Lena River empties into the Laptev Sea dominate the top portions of the images. Creating accurate maps of vegetation structure is essential for understanding the seasonal exchanges of energy and water at the Earth's surface and for preserving biodiversity. The left-hand image is a natural-color image from MISR's nadir (vertical-viewing) camera, in which the rivers appear murky due to sediment, and photosynthetically active vegetation appears green. The center image is also from MISR's nadir camera, but is a false-color view in which the predominant red color is due to the brightness of vegetation at near-infrared wavelengths. Apart from the Lena Delta, the most photosynthetically active regions are within the lower half of the image and throughout the great stretch of land that curves across the Olenek River. Ā The relatively barren ranges of the Volyoi Mountains appear as the pale tan-colored area to the right of image center. The right-hand image is a multiangle, false-color view made from the red band data of the 60-degree-backward, nadir, and 60-degree-forward cameras, displayed as red, green and blue, respectively. Water appears blue in this image because sun glint makes smooth, wet surfaces look brighter at the forward camera's view angle. Much of the landscape and many low clouds appear purple because these surfaces are both forward and backward scattering, and clouds that are further from the surface appear in a different spot for each view angle, creating a rainbow-like appearance. The highly vegetated region in the natural-color nadir image exhibits a faint greenish hue in the multi-angle composite. This subtle effect suggests that the nadir camera is observing more of the brighter, underlying surface than the oblique cameras, providing information about the distribution and density of trees and shrubs in this area. The Multiangle Imaging SpectroRadiometer observes the daylit Earth continuously, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ], provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 24273. The panels cover an area of about 230 kilometers x 420 kilometers, and utilize data from blocks 30 to 34 within World Reference System-2 path 134. 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. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Raytheon/JPL). |
|
Cloud Heights of Frances and
…
| Title |
Cloud Heights of Frances and Ivan |
| Description |
NASA's Multi-angle Imaging SpectroRadiometer [ http://www-misr.jpl.nasa.gov ] (MISR) captured these images and cloud-top height retrievals of Hurricane Frances on September 4, 2004, when the eye sat just off the coast of eastern Florida, and Hurricane Ivan on September 5, after the storm had devastated Grenada and was heading toward the central and western Caribbean. Hurricane Frances made landfall in the early hours of September 5, and was downgraded to Tropical Storm status as it swept inland through the Florida panhandle and continued northward. Following on the heels of Frances is Hurricane Ivan, which is on record as the strongest tropical hurricane to form at such a low latitude in the Atlantic, and was the most powerful storm to have hit the Caribbean in nearly a decade. The ability of forecasters to predict the intensity and amount of rainfall associated with hurricanes still requires improvement, especially on the 24- to 48-hour timescale vital for disaster planning. To improve the operational models used to make hurricane forecasts, scientists need to better understand the multi-scale interactions at the cloud, mesoscale and synoptic scales that lead to hurricane intensification and dissipation, as well as the various physical processes that determine hurricane intensity and rainfall distributions. Because these uncertainties with regard to how to represent cloud processes still exist, it is vital that the model findings be evaluated against hurricane observations whenever possible. Two-dimensional maps of cloud height such as those shown here offer an unprecedented opportunity for comparing simulated cloud fields against actual hurricane observations. The lefthand panel in each image pair is a natural-color view from MISR's nadir camera. The righthand panels are cloud-top height retrievals produced by automated computer recognition of the distinctive spatial features between images acquired at different view angles. These results indicate that at the time that these images were acquired, clouds within Frances and Ivan had attained altitudes of 15-16 kilometers (9-10 miles) above sea level, respectively. The height fields pictured here are uncorrected for the effects of cloud motion. Wind-corrected heights (which have higher accuracy but coarser spatial coverage) are within about 1 kilometer of the heights shown here. (Visit the Earth Observatory's Natural Hazards Severe Storms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?topic=storm ] section to view more recent images of Hurricanes Ivan and Frances.) The MISR observes the daylit Earth continuously and every 9 days views the entire globe between 82Ā° north and 82Ā° south latitude. These data products were generated from a portion of the imagery acquired during Terra [ http://terra.nasa.gov ], orbits 25081 and 25094. The panels cover an area of 380 kilometers x 924 kilometers, and utilize data from within blocks 65 to 87 within World Reference System-2 paths 14 and 222, respectively. 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. NASA image courtesy GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov ] Text acknowledgment: Clare Averill (Raytheon/Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign). |
|
Dust Shrouds the Eastern Med
…
| Title |
Dust Shrouds the Eastern Mediterranean |
| Description |
On October 18, 2002, a large dust plume extended across countries bordering the eastern Mediterranean Sea. Information on the horizontal and vertical extent of the dust are provided by these views from the Multi-angle Imaging SpectroRadiometer (MISR). The left-hand panel portrays the scene as viewed by the instrument's vertical-viewing (nadir) camera. Here only some of the dust over eastern Syria and southeastern Turkey can be discerned. The dust is much more obvious in the center panel, which is a view from MISR's most steeply forward-looking camera. In addition, this perspective makes shadows cast by clouds onto the dust layer more apparent, providing a visual clue that the dust is at a lower altitude than these clouds. The right-hand panel is an elevation field derived from automated MISR stereoscopic processing, in which the heights of clouds and certain parts of the dust plume are retrieved. Because the stereoscopic approach makes use of features within the images that exhibit spatial contrast, heights for much of the dust plume (as well as the ocean surface) could not be retrieved, and these areas are shown in dark gray. Clouds within the image area are situated between about 2 and 5.5 kilometers above sea level, and the dust is located below most of the cloud, at heights of about 1.5 kilometers or less. When the stereo retrieval determines that a location is at a near-surface altitude, digital terrain elevation data are displayed instead. The highest clouds in this scene appear as the orange and red areas, and mountainous regions are displayed in light blue and green. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 15072. The panels cover an area of about 380 kilometers x 827 kilometers, and utilize data from blocks 58 to 65 within World Reference System-2 path 174. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory). |
|
Dust Shrouds the Eastern Med
…
| Title |
Dust Shrouds the Eastern Mediterranean |
| Description |
On October 18, 2002, a large dust plume extended across countries bordering the eastern Mediterranean Sea. Information on the horizontal and vertical extent of the dust are provided by these views from the Multi-angle Imaging SpectroRadiometer (MISR). The left-hand panel portrays the scene as viewed by the instrument's vertical-viewing (nadir) camera. Here only some of the dust over eastern Syria and southeastern Turkey can be discerned. The dust is much more obvious in the center panel, which is a view from MISR's most steeply forward-looking camera. In addition, this perspective makes shadows cast by clouds onto the dust layer more apparent, providing a visual clue that the dust is at a lower altitude than these clouds. The right-hand panel is an elevation field derived from automated MISR stereoscopic processing, in which the heights of clouds and certain parts of the dust plume are retrieved. Because the stereoscopic approach makes use of features within the images that exhibit spatial contrast, heights for much of the dust plume (as well as the ocean surface) could not be retrieved, and these areas are shown in dark gray. Clouds within the image area are situated between about 2 and 5.5 kilometers above sea level, and the dust is located below most of the cloud, at heights of about 1.5 kilometers or less. When the stereo retrieval determines that a location is at a near-surface altitude, digital terrain elevation data are displayed instead. The highest clouds in this scene appear as the orange and red areas, and mountainous regions are displayed in light blue and green. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 15072. The panels cover an area of about 380 kilometers x 827 kilometers, and utilize data from blocks 58 to 65 within World Reference System-2 path 174. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory). |
|
Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid developmentĀ it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
|
Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid developmentĀ it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
|
Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid developmentĀ it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
|
East Coast Snow Storm
| Title |
East Coast Snow Storm |
| Description |
browse image of orbit 15805. (700 KB JPEG) The snowstorm which swept across the eastern United States on December 4 and 5 also brought the season's first snow to parts of the south and southern Appalachia. The extent of snow cover over central Kentucky, eastern Tennessee, western North Carolina and Virginia are apparent in this view from the Multi-angle Imaging SpectroRadiometer (MISR). This natural-color image was captured by MISR's downward-looking (nadir) camera on December 7, 2002. The Appalachians are bounded by the Blue Ridge mountain belt along the east and the Appalachian Plateau along the west. Valleys and ridges between the higher elevation areas retain the green and reddish-brown hues of autumn, and many rivers and lakes appear blue and unfrozen. The highest peak in the eastern United States, Mount Mitchell, is found in North Carolina's western tip, near the Great Smoky Mountains (the dark-colored range at lower right). The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. This data product was generated from a portion of the imagery acquired during Terra orbit 15805. The image covers an area of 347 kilometers x 279 kilometers, and utilizes data from blocks 60 to 62 within World Reference System-2 path 19. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory). |
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Plume from Ol Doinyo Lengai
| Title |
Plume from Ol Doinyo Lengai |
| Description |
In early September 2007, Tanzania's Ol Doinyo Lengai Volcano erupted, sending a cloud of ash into the atmosphere. On September 4, 2007, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite captured this image of the volcano sending a plume of ash and steam southward. The volcanic plume appears pale blue-gray, distinct near the summit, and growing more diffuse to the south. On the land surface, green indicates vegetation, and beige and gray indicate bare or thinly vegetated ground. The charcoal-colored stains on the volcano's flanks appear to be lava, but they are actually burn scars left behind by fires that were spawned by fast-flowing, narrow rivers of lava ejected by the volcano. An explosive eruption of ash and steam is rare for Ol Doinyo Lengai. Typically, volcanic activity at the volcano consists of lava flows that are restricted to the summit crater. This eruption, however, sent ash downwind at least 18 kilometers (11 miles).Ol Doinyo Lengai [ http://www.volcano.si.edu/world/volcano.cfm?vnum=0202-12= ] is an unusual volcano. Like many other volcanoes on Earth, it is a stratovolcano composed of alternating layers of hardened lava, solidified ash, and rocks from previous eruptions. Unlike other volcanoes, however, Ol Doinyo Lengai is the only active volcano on Earth known to produce natrocarbonatite lava. Natrocarbonatite has a relatively low temperature, about 500 to 600 degrees Celsius (930 to 1,100 degrees Fahrenheit), compared to typical lavas, which are about 700 to 1,200 degrees Celsius (1,300 to 2,200 degrees Fahrenheit). Although still hot enough to burn much of what it directly touches, this lava is cool enough to allow close-up inspection without the routine layers of protective gear that volcanologists use elsewhere. But while it is cooler than other lavas, natrocarbonatite lava is also less viscous. Its more fluid consistency means this lava is also faster than other lavas, in fact, it can flow faster than a person can run. Natrocarbonatite lava is composed of minerals that react easily with atmospheric moisture, and exposed lava begins to lighten shortly after eruption. You can download a 15-meter-resolution KMZ file of Ol Doinyo Lengai [ http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/oldoinyo_ast_2007247.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] Thanks to Greg Vaughan, Jet Propulsion Laboratory, for image interpretation. |
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Rice Cultivation in Northwes
…
| Title |
Rice Cultivation in Northwest Italy |
| Description |
The lowlands of Lombardy and Piedmont in northwest Italy are some of the most highly developed irrigation areas in the world. Irrigated lands cover at least 160,000 acres in this part of Italy, where rice is the most important crop. These views of the region were acquired on May 8, 2005, by NASA's Multi-angle Imaging SpectroRadiometer (MISR). The multiple viewing angles provided by MISR's nine cameras make it possible to tell wet surfaces, including flooded lands, from other surfaces, and they also make cities easy to locate. The left-hand image is a natural-color view acquired by MISR's downward-looking (nadir) camera, and the right-hand image is a combination of red band data from MISR's 60-degree-backward-, nadir, and 60-degree-forward-viewing cameras. (Red band is what scientists call the "channel" on the sensor that detects red light.) Color changes indicate surface texture, which is influenced by terrain, vegetation structure, soil type, and surface wetness. Wet surfaces or areas with standing water appear in blue or purple-blue hues. The purple-blue areas that dominate the center-left part of the image are part of the extensive irrigation network that exists throughout the plains and meadows of the region. Cities with tall buildings appear in red-orange hues. In this type of image, the city of Milan is the most obvious. The small orange area in the center of the purple inundated area indicates the location of Vercelli, and the larger city of Milan is the orange area to the northeast, on the other side of the Ticino River. To a lesser extent, the cities of Novara, Pavia, Galliate, Mortara, and Vigevano are also identifiable by their orange hues. MISR can tell various surface features like cities or irrigated areas apart because of the way surfaces reflect light. A smooth water surface tends to reflect sunlight away from the Sun. This effect is most apparent when a satellite views the surface with the Sun in front of the camera. Similarly, rough surfaces tend to reflect light back towards the Sun, and this "backward scattering" is most obvious when a satellites views a surface with the Sun behind the camera. Clouds present over the high country to the west of the Lago Maggiore (upper left corner) and along the coast of the Golfo di Genova (bottom) appear in a different spot for each view angle, creating a rainbow-like appearance. Mountains also have a "wavy" look in the multi-angle combination because, like clouds, their height above the surface makes them appear in a different spot in each camera's view angle. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. This image covers an area of about 131 kilometers by 191 kilometers. These data products were generated from a portion of the imagery acquired during Terra orbit 28660 and utilize data from block 54 within World Reference System-2 path 193. MISR was, built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Raytheon ITSS/JPL) |
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Tropical Cyclone Monty
| Title |
Tropical Cyclone Monty |
| Description |
The Multi-angle Imaging SpectroRadiometer (MISR) acquired these natural color images and cloud top height measurements for Monty before and after the storm made landfall over the remote Pilbara region of Western Australia, on February 29 and March 2, 2004 (shown as the left and right-hand image sets, respectively). On February 29, Monty was upgraded to category 4 cyclone status. After traveling inland about 300 kilometers to the south, the cyclonic circulation had decayed considerably, although category 3 force winds were reported on the ground. Some parts of the drought-affected Pilbara region received more than 300 millimeters of rainfall, and serious and extensive flooding has occurred. The natural color images cover much of the same area, although the right-hand panels are offset slightly to the east. Automated stereoscopic processing of data from multiple MISR cameras was utilized to produce the cloud-top height fields. The distinctive spatial patterns of the clouds provide the necessary contrast to enable automated feature matching between images acquired at different view angles. The height retrievals are at this stage uncorrected for the effects of the high winds associated with cyclone rotation. Areas where heights could not be retrieved are shown in dark gray. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbits 22335 and 22364. The panels cover an area of about 380 kilometers x 985 kilometers, and utilize data from blocks 105 to 111 within World Reference System-2 paths 115 and 113. 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. Image courtesy NASA/GSFC/LaRC/JPL MISR Team [ http://www-misr.jpl.nasa.gov/ ], caption courtesy Clare Averill, Raytheon/Jet Propulsion Laboratory. |
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Jupiter from Voyager
| Title |
Jupiter from Voyager |
| Explanation |
Imagine a hurricane that lasted for 300 years! This picture of the planet Jupiter was taken by the Voyager 1 spacecraft as it passed the planet in 1979. Jupiter, a gas giant planet with no solid surface, is the largest planet in the solar system and is made mostly of the hydrogen and helium. Clearly visible in the photo is the Great Red Spot, a giant, hurricane-like storm system that rotates with the clouds of Jupiter. It is so large three complete Earths could fit inside it. Astronomers have observed this giant storm on Jupiter for over 300 years. For more information see NASA Jet Propulsion Laboratory release. [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/redspot.txt ] |
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Ida and Dactyl: Asteroid and
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| Title |
Ida and Dactyl: Asteroid and Moon |
| Explanation |
An asteroid with a moon! The robot spacecraft Galileo [ http://nssdc.gsfc.nasa.gov/planetary/galileo.html ] whose primary mission is to explore the Jupiter system, has encountered and photographed two asteroids during its long journey to Jupiter. The second asteroid it photographed, called Ida, was discovered to have a moon which appears as a small dot to the right of Ida in this picture. The tiny moon, named Dactyl, is about one mile across, while the potato shaped Ida measures about 36 miles long and 14 miles wide. Dactyl is the first moon of an asteroid ever discovered. The names Ida and Dactyl [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/dactyl.txt ] are based on characters in Greek mythology. For more information see NASA, Jet Propulsion Laboratory press release. [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/idadactyl_false.txt ] |
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