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Jupiter's Moons
On Jan. 7, 1610, Galileo Gal
01/08/10
| Description |
On Jan. 7, 1610, Galileo Galilei's improvements to the telescope enabled humanity to see Jupiter's four largest moons for the first time. Io, Europa, Ganymede and Callisto--the so-called Galilean satellites--were seen by the Long Range Reconnaissance Imager on the New Horizons spacecraft during its flyby of Jupiter in late February 2007. The images have been scaled to represent the true relative sizes of the four moons and are arranged in their order from Jupiter. Io is notable for its active volcanism, which New Horizons studied extensively. On the other hand, Europa's smooth, icy surface likely conceals an ocean of liquid water. New Horizons obtained data on Europa's surface composition and imaged subtle surface features, and analysis of these data may provide new information about the ocean and the icy shell that covers it. New Horizons spied Ganymede from 2.2 million miles away. Ganymede, the largest moon in the solar system, has a dirty ice surface cut by fractures and peppered by impact craters. New Horizons' infrared observations may provide insight into the composition of the moon's surface and interior. Scientists are using the infrared spectra New Horizons gathered of Callisto's ancient, cratered surface to calibrate spectral analysis techniques that will help them to understand the surfaces of Pluto and its moon Charon when New Horizons passes them in 2015. Image Credit: NASA/JHU-APL/Southwest Research Institute |
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01/08/10 |
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As it arrived at Jupiter on
| Description |
As it arrived at Jupiter on December 7, 1995, NASA's Galileo orbiter received a stream of data transmissions -- represented by the blue dots in this artist's depiction -- from the atmospheric probe that was descending through Jupiter's clouds. The orbiter had released the probe five months earlier. The wok-shaped probe sent information to the orbiter for 57.6 minutes as it dropped about 200 kilometers (125 miles) through the atmosphere, before succumbing to atmospheric pressure about 23 times greater than the average at Earth's sea level. The probe returned data about sunlight, heat flux, pressure, temperature, winds, lightning and atmospheric composition. About one hour after the end of the probe's transmissions, the orbiter fired its main engine to brake into orbit around Jupiter. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Galileo mission for NASA's Office of Space Science, Washington, D.C. |
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This 4-panel frame shows a s
| Description |
This 4-panel frame shows a section of Jupiter's North Equatorial Belt viewed by Cassini at 4 different wavelengths on November 27, when the resolution had improved to 192 km/pixel, surpassing the Hubble Space Telescope Wide Field Camera in resolving power. The images have been contrast-enhanced for the purpose of illustration. The upper panel is an image taken in the near-infrared at a wavelength inaccessible to the human eye. The gases in the atmosphere are relatively non-absorbing, allowing sunlight to penetrate deeply into the atmosphere and be reflected back out, thus giving us a direct view of the deeper regions of the troposphere. (On Earth, the troposphere is the portion of the atmosphere closest to the surface, in which most of the atmospheric water vapor resides.) The second panel is taken in the blue at shorter wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the uppermost panel. The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. In this image, dark places are locations of strong absorption (i.e., regions without high-level clouds and consequently large amounts of methane accessible to sunlight), and bright regions are locations with high (upper troposphere) clouds shielding the methane below. The bottom-most panel is an image taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and stratospheric hazes absorb sunlight, both very efficiently, making it difficult to see into the troposphere at all. So bright regions are generally free of high stratospheric hazes. The fascinating aspect of these 4 images is the small bright spot that can be seen in the center of each one. Bright spots similar to this were seen in turbulent regions by the Galileo cameras, and they appear to be very energetic convective storms that move heat from the interior of Jupiter to higher altitudes. These storms are expected to penetrate to great heights, and so it is not surprising to see the storm in the first three images, which probe atmospheric altitudes from the lower to the upper troposphere. What is surprising is the appearance of the spot in the ultraviolet image. This may in fact be a `monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. Higher resolution, time-lapse images to be captured in the coming weeks will shed more light on these spectacular features. Credit: NASA/JPL/University of Arizona |
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Jupiter Eye to Io
This image taken by NASA's C
12/11/00
| Date |
12/11/00 |
| Description |
This image taken by NASA's Cassini spacecraft on Dec. 1, 2000, shows details of Jupiter's Great Red Spot and other features that were not visible in images taken earlier, when Cassini was farther from Jupiter. The picture is a color composite, with enhanced contrast, taken from a distance of 28.6 million kilometers (17.8 million miles). It has a resolution of 170 kilometers (106 miles) per pixel. Jupiter's closest large moon, Io, is visible at left. The edges of the Red Spot are cloudier with ammonia haze than the spot's center is. The filamentary structure in the center appears to spiral outward toward the edge. NASA's Galileo spacecraft has previously observed the outer edges of the Red Spot to be rotating rapidly counterclockwise, while the inner portion was rotating weakly in the opposite direction. Whether the same is true now will be answered as Cassini gets closer to Jupiter and interior cloud features become sharper. Cassini will make its closest approach to Jupiter, at a distance of about 10 million kilometers (6 million miles), on Dec. 30, 2000. The Red Spot region has changed in one notable way over the years: In images from NASA's Voyager and Galileo spacecraft, the area surrounding the Red Spot is dark, indicating relatively cloud-free conditions. Now, some bright white ammonia clouds have filled in the clearings. This appears to be part of a general brightening of Jupiter's cloud features during the past two decades. Jupiter has four large moons and an array of tiny ones. In this picture, Io is visible. The white and reddish colors on Io's surface are due to the presence of different sulfurous materials while the black areas are due to silicate rocks. Like the other large moons, Io always keeps the same hemisphere facing Jupiter, called the sub-Jupiter hemisphere. The opposite side, much of which we see here, is the anti-Jupiter hemisphere. Io has more than 100 active volcanoes spewing very hot lava and giant plumes of gas and dust. Its biggest plume, Pele, is near the bottom left edge of Io's disk as seen here. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona # # # # # |
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Io in Front of Jupiter
Jupiter's four largest satel
12/20/00
| Date |
12/20/00 |
| Description |
Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope. Images from Cassini that will be released over the next several days capture each of the four Galilean satellites in their orbits around the giant planet. This true-color composite frame, made from narrow angle images taken on Dec. 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers (12.1 million miles). The image scale is 117 kilometers (73 miles) per pixel. The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona # # # # # |
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Europa, Callisto and Jupiter
One moment in an ancient, or
12/21/00
| Date |
12/21/00 |
| Description |
One moment in an ancient, orbital dance is caught in this color picture taken by NASA's Cassini spacecraft on Dec. 7, 2000, just as two of Jupiter's four major moons, Europa and Callisto, were nearly perfectly aligned with each other and the center of the planet. The distances are deceiving. Europa, seen against Jupiter, is 600,000 kilometers (370,000 miles) above the planet's cloud tops. Callisto, at lower left, is nearly three times that distance from the cloud tops. Europa is a bit smaller than Earth's Moon and has one of the brightest surfaces in the solar system. Callisto is 50 percent bigger -- roughly the size of Saturn's largest satellite, Titan -- and three times darker than Europa. Its brightness had to be enhanced in this picture, relative Europa's and Jupiter's, in order for Callisto to be seen in this image. Europa and Callisto have had very different geologic histories but share some surprising similarities, such as surfaces rich in ice. Callisto has apparently not undergone major internal compositional stratification, but Europa's interior has differentiated into a rocky core and an outer layer of nearly pure ice. Callisto's ancient surface is completely covered by large impact craters: The brightest features seen on Callisto in this image were discovered by the Voyager spacecraft in 1979 to be bright craters, like those on our Moon. In contrast, Europa's young surface is covered by a wild tapestry of ridges, chaotic terrain and only a handful of large craters. Recent data from the magnetometer carried by the Galileo spacecraft, which has been in orbit around Jupiter since 1995, indicate the presence of conducting fluid, most likely salty water, inside both Callisto and Europa. Scientists are eager to discover whether the surface of Saturn's Titan resembles that of Callisto or Europa, or whether it is entirely different, when Cassini finally reaches its destination in 2004. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona ##### |
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The Main Ring of Jupiter (cl
The ring system of Jupiter w
1/17/97
| Date |
1/17/97 |
| Description |
The ring system of Jupiter was imaged by the Galileo spacecraft on November 9, 1996. In this image the west ansa of Jupiter's main ring is seen at a resolution of 24 kilometers per pixel. The ring clearly shows radial structure that had only been hinted at in the Voyager images. The plot of the brightness of ring as a function of location, going from the inner-most edge of the image to the outer-most through the thickest part of the ring, shows the "dips" in brightness due to perturbations from satellites. Two small satellites, Adrastea and Metis, which are not seen in this image, orbit through the outer portion of the ansa, their location relative to these radial features will be available after further data analysis. The ring's faint halo is seen to arise in the inner main ring just as it fades. Although most of Jupiter's ring is composed of small grains that should be highly perturbed by the strong Jovian magnetosphere, the ring's brightness drops abruptly at the outer edge. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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This is a composite of two i
1/17/97
| Date |
1/17/97 |
| Description |
This is a composite of two images of Jupiter's icy moon Europa obtained from a range of 2119 miles (3410 kilometers) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The mosaic spans 11 miles by 30 miles (17 km by 49 km) and shows features as small as 230 feet (70 meters) across. This mosaic is the first very high resolution image data obtained of Europa, and has a resolution more than 50 times better than the best Voyager coverage and 500 times better than Voyager coverage in this area. The mosaic shows the surface of Europa to be structurally complex. The sun illuminates the scene from the right, revealing complex overlapping ridges and fractures in the upper and lower portions of the mosaic, and rugged, more chaotic terrain in the center. Lateral faulting is revealed where ridges show offsets along their lengths (upper left of the picture). Missing ridge segments indicate obliteration of pre-existing materials and emplacement of new terrain (center of the mosaic). Only a small number of impact craters can be seen, indicating the surface is not geologically ancient. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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This image of Europa, an icy
1/17/97
| Date |
1/17/97 |
| Description |
This image of Europa, an icy satellite of Jupiter, was obtained from a range of 39028 miles (62089 kilometers) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans an area 78 miles by 244 miles (126 km by 393 km), and shows features as small as a mile (1.6 km) across. Sun illumination is from the right, revealing several ridges crossing the scene, plateaus commonly several miles (10 km) across, and patches of smooth, low-lying darker materials. No prominent impact craters are visible, indicating the surface in this location is not geologically ancient. Some ridges have gaps, and subtle textural differences in these areas indicate that missing ridge segments probably were swept away by volcanic flows. The flow deposits are probably composed mainly of water ice, the chief constituent of the surface of Europa. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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Ridges on Europa
This is the highest resoluti
1/17/97
| Date |
1/17/97 |
| Description |
This is the highest resolution picture ever taken of the Jupiter moon, Europa. The area shown is about 5.9 by 9.9 miles (9.6 by 16 kilometers) and the smallest visible feature is about the size of a football field. In this view, the ice-rich surface has been broken into a complex pattern by cross-cutting ridges and grooves resulting from tectonic processes. Sinuous rille- like features and knobby terrain could result from surface modifications of unknown origins. Small craters of possible impact origin range in size from less than 330 feet (100 meters) to about 1300 feet (400 meters) across are visible. This image was taken by the solid state imaging television camera aboard the Galileo during its fourth orbit around Jupiter, at adistance of 2060 miles (3340 kilometers). The picture is centered at 325 degrees West, 5.83 degrees North. North is toward the top of this image, with the sun shining from the right. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL ##### |
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This image of Europa, an icy
1/17/97
| Date |
1/17/97 |
| Description |
This image of Europa, an icy satellite of Jupiter about the size of the Earth's Moon, was obtained from a range of 7415 miles (11933 kilometers) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans 30 miles by 57 miles (48 km by 91 km) and shows features as small as 800 feet (240 meters) across. The large circular feature centered in the upper middle of the image is called a macula, and could be the scar of a large meteorite impact. The surface of Europa is composed mostly of water ice, so large impact craters on Europa could look different from large bowl-shaped depressions formed by impact into rock, such as on the Moon. On Europa's icy surface, the original impact crater has been modified into a central zone of rugged topography surrounded by circular fractures which reflect adjustments to stress in the surrounding icy crust. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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This image of Jupiter's sate
1/17/97
| Date |
1/17/97 |
| Description |
This image of Jupiter's satellite Europa was obtained from a range of 7364 miles (11851 km) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans 30 miles by 57 miles (48 km x 91 km) and shows features as small as 800 feet (240 meters) across, a resolution more than 150 times better than the best Voyager coverage of this area. The sun illuminates the scene from the right. The large circular feature in the upper left of the image could be the scar of a large meteorite impact. Clusters of small craters seen in the right of the image may mark sites where debris thrown from this impact fell back to the surface. Prominent doublet ridges over a mile (1.6 km) wide cross the plains in the right part of the image, younger ridges overlap older ones, allowing the sequence of formation to be determined. Gaps in ridges indicate areas where emplacement of new surface material has obliterated pre-existing terrain. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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Sulfuric Acid on Europa
Frozen sulfuric acid on Jupi
9/1/99
| Date |
9/1/99 |
| Description |
Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain. This image is based on data gathered by Galileo's near infrared mapping spectrometer. Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks. Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA. ##### |
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Aurora Borealis on Jupiter
This image, taken by NASA's
2/10/97
| Date |
2/10/97 |
| Description |
This image, taken by NASA's Galileo spacecraft, shows the dark side of Jupiter, the part not illuminated by sunlight. The curved line crossing from the lower left to the upper right is the auroral arc on the horizon. With north at the top of the image, the central part of the auroral arc has a latitude of 57 degrees north. When this same region was imaged 30 seconds later, the central part had changed. The left and right boxes below show a magnified view of the central region at the earlier and later times, respectively. The aurora is dynamic on Jupiter, just as it is here on Earth. The eerie, glowing light is created when molecules in the upper atmosphere are struck by charge particles from the space around Jupiter. Fluctuations in the charged particle flow cause variations in the auroral emission. This image was part of a multi-instrument set of observations made as Galileo flew through a region of space rich in charged particles. The particles follow the magnetic field and, in this case, the spacecraft was flying through the particular field line that was imaged. With these observations, scientists hope to learn more about the particles and their interaction with the molecules in the atmosphere. This image provides a severe test of the camera optics. The overexposed region at the lower right is the illuminated part of the planet, which is much brighter than the aurora. When light from this region is scattered into the telescope, it creates a diffuse background. The long exposure subjects the detector to more cosmic rays than usual. These create spikes, the bright dots that are sprinkled throughout the image. These images were taken in the clear filter of the solid state imaging (CCD) system aboard the Galileo spacecraft on Nov. 5, 1996. Each pixel subtends a square about 30 kilometers (18.5 miles) throughout the image. The range is 1.433 million kilometers (0.89 million miles). Launched in October 1989, Galileo entered orbit around Jupiter on Dec. 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and its magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are on the Galileo mission home page on the World Wide Web at http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo. ##### |
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Callisto Crater Chain Mosaic
This mosaic of three images
2/10/97
| Date |
2/10/97 |
| Description |
This mosaic of three images shows an area within the Valhalla region on Jupiter's moon, Callisto. North is to the top of the mosaic and the Sun illuminates the surface from the left. The smallest details that can be discerned in this picture are knobs and small impact craters about 160 meters (175 yards) across. The mosaic covers an area approximately 45 kilometers (28 miles) across. It shows part of a prominent crater chain located on the northern part of the Valhalla ring structure. Crater chains can form from the impact of material ejected from large impacts (forming secondary chains) or by the impact of a fragmented projectile, perhaps similar to the Shoemaker-Levy 9 cometary impacts into Jupiter in July 1994. It is believed this crater chain was formed by the impact of a fragmented projectile. The images which form this mosaic were obtained by the solid state imaging system aboard NASA's Galileo spacecraft on Nov. 4, 1996 (Universal Time). Launched in October 1989, Galileo entered orbit around Jupiter on December 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web Galileo mission home page at http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo. ##### |
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False Color Mosaic of Jupite
This false color mosaic show
2/10/97
| Date |
2/10/97 |
| Description |
This false color mosaic shows a belt-zone boundary near Jupiter's equator. The images that make up the four quadrants of this mosaic were taken within a few minutes of each other. Light at each of Galileo's three near-infrared wavelengths is displayed here in the visible colors red, green and blue. Light at 886 nanometers, strongly absorbed by atmospheric methane and scattered from clouds high in the atmosphere, is shown in red. Light at 732 nanometers, moderately absorbed by atmospheric methane, is shown in green. Light at 757 nanometers, scattered mostly from Jupiter's lower visible cloud deck, is shown in blue. The lower cloud deck appears bluish white, while the higher layer appears pinkish. The holes in the upper layer and their relationships to features in the lower cloud deck can be studied in the lower half of the mosaic. Galileo is the first spacecraft to image different layers in Jupiter's atmosphere. The edge of the planet runs along the right side of the mosaic. North is at the top. The mosaic covers latitudes -13 to +3 degrees and is centered at longitude 280 degrees west. The smallest resolved features are tens of kilometers in size. These images were taken on Nov. 5, 1996, at a range of 1.2 million kilometers by the solid state imaging (CCD) system aboard NASA's Galileo spacecraft. Launched in October 1989, Galileo entered orbit around Jupiter on Dec. 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web Galileo mission home page at http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo. ##### |
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Asgard Scarp Mosaic
Low-resolution color data we
2/10/97
| Date |
2/10/97 |
| Description |
Low-resolution color data were combined with a higher resolution mosaic to produce this infrared composite image of a pair of ancient multi-ringed impact basins on Jupiter's moon, Callisto. The region imaged is on the leading hemisphere of Callisto near 26 degrees north, 142 degrees west, and is almost 1,400 kilometers (860 miles) across. North is toward the top of the picture and the Sun illuminates the surface from the east. Dominating the scene is the impact structure, Asgard, centered on the smooth, bright region near the middle of the picture and surrounded by concentric rings up to 1,700 kilometers (about 1,050 miles) in diameter. A second ringed structure with a diameter of about 500 kilometers (310 miles) can be seen to the north of Asgard, partially obscured by the more recent, bright- rayed crater, Burr. The icy materials excavated by the younger craters contrast sharply with the darker and redder coatings on older surfaces of Callisto. Launched in October 1989, Galileo entered orbit around Jupiter on Dec. 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web Galileo mission home page at http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo. ##### |
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Jupiter Equatorial Region
True and false color views o
6/5/97
| Date |
6/5/97 |
| Description |
True and false color views of Jupiter from NASA's Galileo spacecraft show an equatorial 'hotspot' on Jupiter. These images cover an area 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles). The top mosaic combines the violet and near infrared continuum filter images to create an image similar to how Jupiter would appear to human eyes. Differences in coloration are due to the composition and abundances of trace chemicals in Jupiter's atmosphere. The bottom mosaic uses Galileo's three near-infrared wavelengths displayed in red, green, and blue) to show variations in cloud height and thickness. Bluish clouds are high and thin, reddish clouds are low, and white clouds are high and thick. The dark blue hotspot in the center is a hole in the deep cloud with an overlying thin haze. The light blue region to the left is covered by a very high haze layer. The multicolored region to the right has overlapping cloud layers of different heights. Galileo is the first spacecraft to distinguish cloud layers on Jupiter. North is at the top. The mosaic covers latitudes 1 to 10 degrees and is centered at longitude 336 degrees west. The smallest resolved features are tens of kilometers in size. These images were taken on December 17, 1996, at a range of 1.5 million kilometers (about 930,000 miles) by the Solid State Imaging camera system aboard Galileo. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/galileo. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo ##### |
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Jupiter's Main Ring and Halo
The top and bottom panels sh
9/15/98
| Date |
9/15/98 |
| Description |
The top and bottom panels show a mosaic of images of Jupiter's rings taken by NASA's Galileo spacecraft. Jupiter is to the right of this mosaic, and different brightness scales accent different parts of the ring system. Jupiter's ring system has three parts -- a flat main ring, a halo inside the main ring shaped like a double-convex lens, and the gossamer ring outside the main ring. In the top view, a faint mist of particles is seen above and below the main rings. This vertically extended "halo" is unusual in planetary rings, and is caused by electromagnetic forces pushing the smallest grains, which carry electric charges, out of the ring plane. Jupiter's main ring is a thin sheet of material encircling the planet. The near and far arms of this ring extend horizontally across the mosaic, joining together at the ring's ansa, the portion visible on the sides of Jupiter, on the figure's far left side. In the bottom view, some radial structure is visible across the ring's ansa. The diffuse innermost boundary begins at approximately 122,500 kilometers (about 76,100 miles). The main ring's outer radius is at about 128,940 kilometers (80,120 miles), very close to the orbit of the Jovian moon Adrastea (128,980 kilometers or 80,140 miles). The brightness of the main ring drops markedly at about 127,850 kilometers (79,440 miles), very near the orbit of another moon, Metis, at 127,978 kilometers (79,521 miles). Jupiter's four small satellites-Metis, Adrastea, Amalthea and Thebe, affect the structure of the huge planet's tenuous rings. These images were taken through the clear filter of Galileo's onboard solid state imaging camera system on November 9, 1996. The resolution is approximately 24 kilometers (14 miles) per picture element along Jupiter's rings. Because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened vertically. The images were obtained when Galileo was in Jupiter's shadow, peering back toward the Sun, when the ring was approximately 2.3 million kilometers (1.4 million miles) away. The view of Earth's moon in the explanatory graphics was created from images returned by the Clementine lunar orbiter, launched in 1994 by NASA and the Ballistic Missile Defense Organization.) JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. The images are posted on the Internet at http://photojournal.jpl.nasa.gov/ and at http://www.jpl.nasa.gov/galileo . Background information and educational context for the images can be found at: http://www.jpl.nasa.gov/galileo/sepo . ##### 9/9/98 JP |
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Shapes of the Small Inner Sa
The upper series of images r
9/15/98
| Date |
9/15/98 |
| Description |
The upper series of images represents the best yet of the four small inner satellites of Jupiter taken by the camera on NASA's Galileo spacecraft. From left to right, in order of decreasing distance to Jupiter, are Thebe, Amalthea (the largest moon), Adrastea (the smallest), and Metis. The images represent the first time that the shapes of Adrastea and Metis have been resolved by a spacecraft camera. The views are presented at a common scale but were taken at somewhat different original resolutions, ranging from 5.4 kilometers (3.3 miles) per picture element for Amalthea, to 7.5 kilometers (4.6 miles) per picture element for Thebe and Metis. Individual craters, 35 to 90 kilometers (20 to 55 miles) across, are visible on Thebe and Amalthea. While no craters are visible on Adrastea and Metis in these images, the overall irregular shape of Metis indicates it has suffered major collisions. Jupiter is to the right. Viewing positions are slightly different from the views of the models in the bottom row, which depict the shapes of the small satellites viewed from the direction of satellite motion ("leading sides") and presented at a common scale. These shape models have been calculated from the outlines of the satellites and locations of shadows in individual images, as well as from stereoscopic images taken by the Galileo's camera during different orbits. The models emphasize the highly irregular shapes caused by a history of impacts by fragments of small asteroids and comets. Jupiter's strong gravitational pull on these objects at relatively close distances accelerates the objects to very high velocities, making such impacts very energetic. JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. The images are posted on the Internet at http://photojournal.jpl.nasa.gov/ and at http://www.jpl.nasa.gov/galileo . Background information and educational context for the images can be found at: http://www.jpl.nasa.gov/galileo/sepo . ##### 9/9/98 JP |
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Jupiter's Inner Satellites a
This schematic cut-away view
9/15/98
| Date |
9/15/98 |
| Description |
This schematic cut-away view of the components of Jupiter's ring system shows the geometry of the rings in relation to Jupiter and to the small inner satellites, which are the source of the dust that forms the rings. The innermost and thickest ring, shown in gray shading, is the halo that ends at the main ring. The thin, narrow main ring, shown with red shading, is bounded by the 16-kilometer-wide (10-miles) satellite Adrastea and shows a marked decrease in brightness near the orbit of Jupiter's innermost moon, Metis. It is composed of fine particles knocked off Adrastea and Metis. Although the orbits of Adrastea and Metis are about 1,000 kilometers (about 600 miles) apart, that separation is not depicted in this drawing. Impacts by small meteoroids (fragments of asteroids and comets) into these small, low- gravity satellites feed material into the rings. Thebe and Amalthea, the next two satellites in increasing distance from Jupiter, supply dust which forms the thicker, disk-like "gossamer" rings. The gossamer rings, depicted with yellow and green shading, are thicker because the source satellites orbit Jupiter on inclined paths These small satellites all orbit closer to Jupiter than the four largest "Galilean" satellites, Io, Europa, Ganymede and Callisto, which were discovered nearly 400 years ago. The orbital distances of the moons are drawn relative to the size of Jupiter. The Jupiter image was created from a map based on data obtained by the Hubble Space Telescope. JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. The images are posted on the Internet at http://photojournal.jpl.nasa.gov/ and at http://www.jpl.nasa.gov/galileo . Background information and educational context for the images can be found at: http://www.jpl.nasa.gov/galileo/sepo . ##### 9/10/98 JP |
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GLL/EM15
This mosaic picture of the M
12/22/92
| Date |
12/22/92 |
| Description |
This mosaic picture of the Moon was compiled from 18 images taken with a green filter by Galileo's imaging system during the spacecraft's flyby on December 7, 1992, some 11 hours before its Earth flyby at 1509 UTC (7:09 a.m. Pacific Standard Time) December 8. The north polar region is near the top part of the mosaic, which also shows Mare Imbrium, the dark area on the left, Mare Serenitatis at center, and Mare Crisium, the circular dark area to the right. Bright crater rim and ray deposits are from Copernicus, an impact crater 96 kilometers (60 miles) in diameter. Computer processing has exaggerated the brightness of poorly illuminated features near the day/night terminator in the polar regions, giving a false impression of high reflectivity there. The digital image processing was done by DLR the German aerospace research establishment near Munich, an international collaborator in the Galileo mission. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory. ##### |
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Jupiter's Main and Gossamer
The schematic structures of
9/15/98
| Date |
9/15/98 |
| Description |
The schematic structures of Jupiter's main and gossamer rings are depicted here. Scientists studying data from NASA's Galileo spacecraft have found that the ring system is made up of impact debris created when meteoroids, which are fragments of comets and asteroids, slam into Jupiter's four smallest satellites. The top panel shows that the main ring (red) is formed mostly from meteoroid impact debris kicked up from the innermost moons, Metis (m) and Adrastea (a). Since both satellites orbit in paths not inclined to Jupiter's equator, the main ring appears as a narrow line. The middle panel shows the additional effect of dust ejected from the satellite Amalthea (A), responsible for producing one of the two moon components of the gossamer ring. Amalthea's orbit is inclined to Jupiter's equatorial plane, and at different times the satellite's vertical position can range anywhere between the two extreme limits shown. Dust ejected from Amalthea (orange) produces a ring whose thickness equals Amalthea's vertical projections beyond Jupiter's equatorial plane. The lower panel shows the additional effect of dust ejected from Thebe (T), which makes up the second component (shown in green) of the gossamer ring. Again, the two positions shown represent the maximum projections of Thebe from Jupiter's equatorial plane. This component of the gossamer ring is thicker than the component due to Amalthea's dust because Thebe's orbit is more inclined than that of Amalthea. The Jupiter image was created from a map based on data obtained by the Hubble Space Telescope. The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. The images are posted on the Internet at http://photojournal.jpl.nasa.gov/ and at http://www.jpl.nasa.gov/galileo . Background information and educational context for the images can be found at: http://www.jpl.nasa.gov/galileo/sepo . ##### 9/9/98 JP |
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GLL/EM16
This view looking down on th
| Description |
This view looking down on the north pole of the Moon was assembled from 18 images taken with a green filter by Galileo's imaging system as the spacecraft flew by the Moon on December 7, 1992. The part of the moon visible from Earth is toward the left and includes the dark, lava-filled Imbrium basin, upper left, Mare Serenitatis, middle left, Mare Tranquillitatis, lower left, and Crisium, the dark circular feature toward the bottom of the mosaic. Also visible in this view are the dark lava plains of the Marginis and Smythii basins, lower right. The Humboldtianum Basin, a 650-kilometer (400-mile) impact structure partly filled with dark volcanic deposits, is visible in the middle of the image. The Moon's north pole is located just inside the shadow zone about a third of the way from the top left of the lighted region. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory. ##### |
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GLL/EM17
This false-color mosaic was
12/22/92
| Date |
12/22/92 |
| Description |
This false-color mosaic was constructed from a series of 53 images taken through three spectral filters by Galileo's imaging system as the spacecraft flew over the northern regions of the Moon on December 7, 1992. The part of the Moon vlsible from Earth is on the left side in this view. The color mosaic shows compositional variations in parts of the Moon's northern hemisphere. Bright pinkish areas are highlands materials, such as those surrounding the oval lava-filled Crisium impact basin toward the bottom of the picture. B1ue to orange shades indicate volcanic lava flows. To the left of Crisium, the dark blue Mare Tranquillitatis is richer in titanium than the green and orange maria above it. Thin mineral-rich soils associated with relatively recent impacts are represented by light blue colors, the youngest craters have prominent blue rays extending from them. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory. ##### |
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This composite image shows t
5/25/94
| Date |
5/25/94 |
| Description |
This composite image shows the asteroid 243 Ida as seen from the Galileo spacecraft during its approach on August 28, 1993. The six views were shuttered through the camera's green filter and show Ida's rotation over a period of about 3 hours 18 minutes. The asteroid makes a complete rotation every 4 hours 38 minutes, therefore, this set of images spans about 3/4 of Ida's rotation period and shows most of Ida's surface. By combining the information in these views with that from the highest resolution images returned from the spacecraft in September 1993, the size and shape of this irregular body can now be determined accurately The asteroid appears to be about 58 kilometers (36 miles) long and about 23 kilometers wide, with a very irregular shape and volume of some 16,000 cubic kilometers. The images are arranged in chronological order from a time 3 hours 51 minutes before closest approach (upper left), through upper right, middle left, middle right lower left and lower right (33 minutes before closest approach). The six images show ida at the same scale throughout. Ida's rotation axis is roughly vertical in these images, and the rotation causes the right-hand end of Ida to move toward the viewer as time progresses. The first image was taken from a range of about 171,000 km (106,000 miles) and provides an inage resolution of about 1,700 meters per pixel (the highest resolution achieved for Ida is about 25 meters per pixel). The second, taken 70 minutes later, is fromOn 119,000 kilometers, followed by 102,000 kilometers, 85,000 kilometers, 50,000 kilometers, and 25,000 kilometers. The features on Ida are less sharp in the earlier views because of the greater distances. Prominent in the middle three views is a deep depression across the short axis of the Asteroid. This feature tends to support the idea that Ida may have originally been formed from two or more separate large objects that collided softly and stuck together. Also visible in the lower left view is an apparent linear albedo or reflectance boundary. Color images yet to be returned from the Galileo spacecrart may help resolve the question of whether or not the two ends of Ida are made of different materials. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory. |
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GALILEO
The Galileo imaging system c
5/25/94
| Date |
5/25/94 |
| Description |
The Galileo imaging system captured this picture of the limb of the asteroid 243 Ida about 46 seconds after its closest approach on August 28, 1993, from a range of only 2480 kilometers. It is the highest-resolution image of an asteroid's surface ever captured and shows detail at a scale of about 25 meters per pixel. This image is one frame of a mosaic of 15 frames shuttered near Galileo's closest approach to Ida. Since the exact location of Ida in space was not well-known prior to the Galileo flyby, this mosaic was estimated to have only about a 50 percent chance of capturing Ida. Fortunately, this single frame did successfully image a part of the sunlit side of Ida. The area seen in this frame shows some of the same territory seen in a slightly lower resolution full-disk mosaic of Ida returned from the spacecraft in September, 1993, but from a different perspective. Prominent in this view is a 2-kilometer- deep "valley" seen in profile on the limb. This limb profile and the stereoscopic effect between this image and the full-disk mosaic will permit detailed refinement of Ida's shape in this region. This high-resolution view shows many small craters and some grooves on the surface of Ida, which give clues to understanding the history of this heavily impacted object. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science by the Jet Propulsion Laboratory. ##### |
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GALILEO
This image is the most detai
6/22/94
| Date |
6/22/94 |
| Description |
This image is the most detailed picture of the recently discovered natural satellite of asteroid 243 Ida taken by the Galileo Solid-State Imaging camera during its encounter with the asteroid on August 28, 1993. Shuttered through the camera's broadband clear filter as part of a 30-frame mosaic designed to image the asteroid itself, this frame fortuitously captured the previously unknown moon at a range of about 3,900 kilometers (2,400 miles), just over 4 minutes before the spacecraft's closest approach to Ida. Each picture element spans about 39 meters (125 feet) on the surface of the moon. More than a dozen craters larger than 80 meters (250 feet) in diameter are clearly evident, indicating that the moon has suffered numerous collisions from smaller Solar System debris during its history. The larger crater on the terminator is about 300 meters (1,000 feet) across. The satellite is approximately egg-shaped, measuring about 1.2 x 1.4 x 1.6 kilometers (0.75 x 0.87 x 1 mile). At the time this image was shuttered, Ida was about 90 kilometers (56 miles) away from the moon, outside this frame to the left and slightly below center. This image was relayed to Earth from Galileo on June 8, 1994. The Galileo project, whose primary mission is the exploration of the Jupiter system in 1995-97, is managed for NASA's Office of Space Science by the Jet Propulsion Laboratory. ##### |
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Europa: Sea Salts or Battery
This composite image of the
4/19/00
| Date |
4/19/00 |
| Description |
This composite image of the Jupiter-facing hemisphere of Europa was obtained on November 25, 1999 by two instruments onboard NASA's Galileo spacecraft. The global black-and-white view, by the spacecraft's camera, provides the highest resolution view ever obtained of this side of Europa. The superimposed false-color image, obtained by Galileo's near-infrared mapping spectrometer instrument, reveals the presence of materials with differing compositions on Europa's surface. In this image, blue areas represent the cleanest, brightest icy surfaces, while the reddest areas have the highest concentrations of darker, non-ice materials. The mixture of colors seen here is most likely the result of both variations in the ages and composition of surface materials. The dark materials are believed to fade with the passage of time. This area is highly unusual compared to many other areas on Europa because of its high concentration of fresh-appearing bright ridges and fractures. On other parts of Europa, the darker areas appear to be the most recently formed, but here the ridges and fractures appear to "overprint" the underlying darker mottled terrain. Scientists disagree about the chemical makeup of the dark materials, both sulfuric acid (common battery acid) and salty minerals, perhaps from a subsurface ocean, have been suggested. Analysis of images like this one may help to resolve this controversy. Surprisingly, either material could help to produce conditions below the surface that could be favorable to the formation of living organisms. The colored area is centered near the intersection of the equator and the Europan "prime meridian," where the longitude is assigned the value of 0 degrees. This is the sub-Jupiter point, where Jupiter always appears to be almost directly overhead. This phenomenon occurs because Europa takes the same period of time to rotate as it does to orbit around Jupiter (3.55 days). The area imaged in color is about 400 by 400 kilometers (250 by 250 miles), an area of about 160,000 square kilometers (about 62,000 square miles). The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is a division of the California Institute of Technology, Pasadena, CA. This image and other images and data received from Galileo are posted on the Galileo home page at http://galileo.jpl.nasa.gov . Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/images/io/ioimages.html . ##### |
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Jupiter small satellite mont
A montage of images of the s
4/24/00
| Date |
4/24/00 |
| Description |
A montage of images of the small inner moons of Jupiter from the camera onboard NASA's Galileo spacecraft shows the best views obtained of these moons during Galileo's 11th orbit around the giant planet in November 1997. At that point, Galileo was completing its first two years in Jupiter orbit -- known as the Galileo "prime mission" -- and was about to embark on a successful two-year extension, called the Galileo Europa Mission. The top two images show the moon Thebe. Thebe rotated by approximately 50 degrees between the time these two images were taken, so that the same prominent impact crater is seen in both views, this crater, which has been given the provisional name Zethus, is near the point on Thebe that faces permanently away from Jupiter. The next two images show the moon Amalthea, they were taken with the Sun directly behind the observer, an alignment that emphasizes patterns of intrinsically bright or dark surface material. The third image from the top is a view of Amalthea's leading side, the side of the moon that "leads" as Amalthea moves in its orbit around Jupiter. This image looks "noisy" because it was obtained serendipitously during an observation of the Jovian satellite Io (Amalthea and Io shared the same camera frame but the image was exposed for bright Io rather than for the much darker Amalthea). The fourth image from the top emphasizes prominent "spots" of relatively bright material that are located near the point on Amalthea that faces permanently away from Jupiter. The bottom image is a view of the tiny moon Metis. In all the images, north is approximately up, and the moons are shown in their correct relative sizes. The images are, from top to bottom: Thebe taken on November 7, 1997 at a range of 504,000 kilometers (about 313,000 miles), Thebe on November 7, 1997 at a range of 548,000 kilometers (about 340,000 miles), Amalthea on November 6, 1997 at a range of about 650,000 kilometers (about 404,000 miles), Amalthea on November 7, 1997 at a range of 475,000 kilometers (about 295,000 miles), Metis on November 7, 1997 at a range of 637,000 kilometers (about 396,000 miles). # # # # # |
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Galileo and Cassini Image: T
Two Giant Plumes on Io ,Two
3/29/01
| Date |
3/29/01 |
| Description |
Two Giant Plumes on Io ,Two tall volcanic plumes and the rings of red material they have deposited onto surrounding surface areas appear in images taken of Jupiter's moon Io by NASA's Galileo and Cassini spacecraft in late December 2000 and early January 2001. One plume, from the volcano Pele, shoots upward nearly 400 kilometers (250 miles) from the surface near Io's equator. The plume has been active for at least four years and, until now, had been far larger than any other plume seen on Io. The images also show a second plume about the same size, closer to Io's north pole. This plume had never been seen before. It is associated with a fresh eruption from the Tvashtar Catena volcanic area. The observations were made during joint studies of the Jupiter system while Cassini was passing Jupiter on its way to Saturn. Galileo passed closer to Io for higher-resolution images, and Cassini acquired images at ultraviolet wavelengths, better for detecting active volcanic plumes. The Cassini ultraviolet images, upper right, reveal two gigantic, actively erupting plumes of gas and dust. Near the equator, just the top of Pele's plume is visible where it projects into sunlight. None of it would be illuminated if it were less than 240 kilometers (150 miles) high. These images indicate a total height for Pele of 390 kilometers (242 miles). The Cassini image at far right shows a bright spot over Pele's vent. Although the Pele hot spot has a high temperature, silicate lava cannot be hot enough to explain a bright spot in the ultraviolet, so the origin of this bright spot is a mystery, but it may indicate that Pele was unusually active when the picture was taken. Also visible is a plume near Io's north pole. Although 15 active plumes over Io's equatorial regions have been detected in hundreds of images from NASA's Voyager and Galileo spacecraft, this is the first image ever acquired of an active plume over a polar region of Io. The plume projects about 150 kilometers (about 90 miles) over the limb, the edge of the globe. If it were erupting from a point on the limb, it would be only slightly larger than a typical Ionian plume, but the image does not reveal whether the source is actually at the limb or beyond it, out of view. A distinctive feature in Galileo images since 1997 has been a giant red ring of Pele plume deposits about 1,400 kilometers (870 miles) in diameter. The Pele ring is seen again in one of the new Galileo images, lower left. When the new Galileo images were returned this month, scientists were astonished to see a second giant red ring on Io, centered around Tvashtar Catena at 63 degrees north latitude. (To see a comparison from before the ring was deposited, see images PIA-01604 or PIA-02309.) Tvashtar was the site of an active curtain of high-temperature silicate lava imaged by Galileo in November 1999 and February 2000 (image PIA- 02584). The new ring shows that Tvashtar must be the vent for the north polar plume imaged by Cassini from the other side of Io. This means the plume is actually about 385 kilometers (239 miles) high, just like Pele. The uncertainty in estimating the height is about 30 kilometers (19 miles), so the plume could be anywhere from 355 to 415 kilometers (221 to 259 miles) high. If this new plume deposit is just one millimeter (four one- hundredths of an inch) thick, then the eruption produced more ash than the 1980 eruption of Mount St. Helens in Washington. NASA recently approved a third extension of the Galileo mission, including a pass over Io's north pole in August 2001. The spacecraft's trajectory will pass directly over Tvashtar at an altitude of 200 kilometers (124 miles). Will Galileo fly through an active plume? That depends on whether this eruption is long- lived like Pele or brief, and it also depends on how high the plume is next August. Two Pele-sized plumes are inferred to have erupted in 1979 during the four months between Voyager 1 and Voyager 2 flybys, as indicated by new Pele-sized rings in Voyager 2 images. Those eruptions, both from high-latitude locations, were shorter-lived than Pele, but their actual durations are unknown. In May, Galileo will get another, more distant look at Tvashtar. It has been said that Io is the heartbeat of the jovian magnetosphere. The two giant plumes evidenced in these images may have had significant effects on the types, density and distribution of neutral and charged particles in the Jupiter system during the joint observations of the system by Galileo and Cassini from November 2000 to March 2001. These Cassini images were acquired on Jan. 2, 2001, except for the frame at the far right, which was acquired a day earlier. The Galileo images were acquired on Dec. 30 and 31, 2000. Cassini was about 10 million kilometers (6 million miles) from Io, 10 times farther than Galileo. 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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Jupiter's Great Red Spot in
This true color image of Jup
10/23/00
| Date |
10/23/00 |
| Description |
This true color image of Jupiter, taken by NASA's Cassini spacecraft, is composed of three images taken in the blue, green and red regions of the spectrum. All images were taken from a distance of 77.6 million kilometers (48.2 million miles) on Oct. 8, 2000. Different chemical compositions of the cloud particles lead to different colors. The cloud patterns reflect different physical conditions -- updrafts and downdrafts -- in which the clouds form. The bluish areas are believed to be regions devoid of clouds and covered by high haze. The Great Red Spot (below and to the right of center) is a giant atmospheric storm as wide as two Earths and over 300 years old, with peripheral winds of 483 kilometers per hour (300 miles per hour). This image shows that it is trailed to the north by a turbulent region, caused by atmospheric flow around the spot. The bright white spots in this region are lightning storms, which were seen by NASA's Galileo spacecraft when it photographed the night side of Jupiter. Cassini will track these lightning storms and measure their lifetimes and motions when it passes Jupiter in late December and looks back on the dark side of the planet. Cassini is currently en route to its ultimate destination, Saturn. The resolution is 466 kilometers (290 miles) per picture element. 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, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. Credit: NASA/JPL/University of Arizona ##### |
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Still from Red Spot Movie
This image is one of seven f
11/20/00
| Date |
11/20/00 |
| Description |
This image is one of seven from the narrow-angle camera on NASA's Cassini spacecraft assembled as a brief movie of cloud movements on Jupiter. It was taken with a blue filter. The smallest features visible are about 500 kilometers (about 300 miles) across. Small bright clouds appear suddenly to the west of the Great Red Spot. Based on data from NASA's Galileo spacecraft, scientists suspect that these small white features are lightning storms, where falling raindrops create an electrical charge. The lightning storms eventually merge with the Red Spot and surrounding jets, and may be the main energy source for these large-scale features. Imaging observations of the dark side of the planet in the weeks following Cassini's closest approach to Jupiter on Dec. 30, 2000 will search for lightning storms like these. This image was re-projected by cylindrical-map projection of an image taken in the first week of October 2000. It shows an area from 50 degrees north of Jupiter's equator to 50 degrees south, extending 100 degrees east-west, about one quarter of Jupiter's circumference. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona # # # # # |
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Galileo at Jupiter
This artist's rendering show
7/11/95
| Date |
7/11/95 |
| Description |
This artist's rendering shows the Galileo orbiter arriving at Jupiter on Dec. 7, 1995. A few hours before arrival, the orbiter will have flown within about 1,000 kilometers (600 miles) of Jupiter's moon lo, shown as the crescent to the left of the spacecraft. The sun is visible between Io and the spacecraft, near the spacecraft's long magnetometer. Jupiter is to the right. A faint white streak above the planet's clouds shows the atmospheric probe beginning to decelerate before it deploys a parachute for its scientific mission to collect data as it descends into the atmosphere and relay that data to the orbiter. About an hour after the probe's mission is over, the orbiter will brake with its rocket engine to go into orbit around Jupiter for a two-year, 11-orbit study of Jupiter, its satellites and its magnetosphere. The Galileo mission is managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, D.C. The Galileo probe is managed by NASA's Ames Research Center, Moffett Field. Calif. |
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Jupiter in color, by Cassini
This color image of Jupiter
10/9/00
| Date |
10/9/00 |
| Description |
This color image of Jupiter was taken by the camera onboard NASA's Cassini spacecraft when it was 81.3 million kilometers (50.5 million miles) from the planet. It is composed of images taken in the blue, green, and red regions of the spectrum and is therefore close to the true color of Jupiter that one would see through an Earth-based telescope. The image is remarkably similar to images taken by NASA's Voyager 1 and 2 spacecraft more than 21 years ago, illustrating the stability of Jupiter's weather patterns. The parallel dark and bright bands and many other large-scale features are quasi- permanent structures that survive despite the intense small-scale activity ongoing in the atmosphere. The longevity of the large- scale features is an intrinsic property of the atmospheric flows on a gaseous planet such as Jupiter, with no solid surface. Smaller features, such as those in the dark bands north and south of the equator, are observed to form and disappear in a few days. Everything visible on the planet is a cloud. Unlike Earth, where only water condenses to form clouds, Jupiter has several cloud-forming substances in its atmosphere. The updrafts and downdrafts bring different mixtures of these substances up from below, leading to clouds of different colors. The bluish features just north of the equator are regions of reduced cloud cover, similar to the place where the Galileo atmospheric probe entered in 1995. They are called "hot spots" because the reduced cloud cover allows heat to escape from warmer, deeper levels in the atmosphere. Jupiter's moon Europa is seen at the right, casting a shadow on the planet. Scientists believe Europa holds promise of a liquid ocean beneath its surface. 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, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. Credit: NASA/JPL/University of Arizona |
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Giant Landslide on Iapetus
| Description |
Giant Landslide on Iapetus |
| Full Description |
A spectacular landslide within the low-brightness region of Iapetus's surface known as Cassini Regio is visible in this image from Cassini. Iapetus is one of the moons of Saturn. The landslide material appears to have collapsed from a scarp 15 kilometers high (9 miles) that forms the rim of an ancient 600 kilometer (375 mile) impact basin. Unconsolidated rubble from the landslide extends halfway across a conspicuous, 120-kilometer diameter (75-mile) flat-floored impact crater that lies just inside the basin scarp. Landslides are common geological phenomena on many planetary bodies, including Earth and Mars. The appearance of this landslide on an icy satellite with low-brightness cratered terrain is reminiscent of landslide features that were observed during NASA's Galileo mission on the Jovian satellite Callisto. The fact that the Iapetus landslide traveled many kilometers from the basin scarp could indicate that the surface material is very fine-grained, and perhaps was fluffed by mechanical forces that allowed the landslide debris to flow extended distances. In this view, north is to the left of the picture and solar illumination is from the bottom of the frame. The image was obtained in visible light with the Cassini spacecraft narrow angle camera on Dec. 31, 2004, at a distance of about 123,400 kilometers (76,677 miles) from Iapetus and at a Sun-Iapetus-spacecraft, or phase, angle of 78 degrees. Resolution achieved in the original image was 740 meters (2,428 feet) per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility. 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 team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . For images visit the Cassini imaging team home page http://ciclops.org . Credit: NASA/JPL/Space Science Institute |
| Date |
January 7, 2005 |
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The Adventure Ahead
| 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. |
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This majestic view of Saturn captures several phenomena of interest to scientists working on the Cassini mission. The planet's nighttime atmosphere looms ahead -- an excellent place to search for storms and lightning. Saturn's shadow stretches across the rings, which will over the next four years receive their most thorough examination since Galileo discovered them in 1610. And barely visible near lower right just inside the F ring, is the small shepherd moon Prometheus (102 kilometers, or 63 miles across). Researchers will explore the many moons of Saturn, including special ones like Prometheus that help maintain some of the rings and gaps in this complex and dynamic system. The image was taken in visible light with the Cassini spacecraft wide angle camera on Oct. 29, 2004, at a distance of about 940,000 kilometers (584,000 miles) from Saturn. The image scale is 52 kilometers (33 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 Science Mission Directorate, 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/Space Science Institute |
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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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A four-panel frame shows a section of Jupiter's north equatorial belt viewed by NASA's Cassini spacecraft at four different wavelengths, and a separate reference frame shows the location of the belt on the planet. A fascinating aspect of the images in the four-panel frame is the small bright spot in the center of each. The images come from different layers of the atmosphere, so the spot appears to be a storm penetrating upward through several layers. This may in fact be a `monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. These images were taken on Nov. 27, 2000, at a resolution of 192 kilometers (119 miles) per pixel. They have been contrast-enhanced to highlight features in the atmosphere. The top panel of the four-panel frame is an image taken in a near-infrared wavelength at which the gases in Jupiter's atmosphere are relatively non-absorbing. Sunlight can penetrate deeply into the atmosphere at this wavelength and be reflected back out, providing a view of an underlying region of the atmosphere, the lower troposphere. The second panel was taken in the blue portion of wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the top panel. The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. Dark places are regions without high-level clouds and consequently large amounts of methane accessible to sunlight. Bright regions are locations with high clouds in the upper troposphere shielding the methane below. The bottom panel was taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and hazes in the stratosphere, above the troposphere, absorb sunlight. That makes it difficult to see into lower layers at all. The bright regions are generally free of high stratospheric hazes. A small bright spot is visible near the center of each panel. Similar spots have been imaged in turbulent regions by the Galileo spacecraft, and they appear to be very energetic convective storms that move heat from the interior of Jupiter to higher altitudes. These storms are expected to penetrate to great heights, and so it is not surprising to see the storm in the first three images, which probe atmospheric altitudes from the lower to the upper troposphere. What is surprising is the appearance of the spot in the ultraviolet image. Higher resolution, time-lapse images to be captured by Cassini in coming weeks will shed more light on these spectacular features. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope. Images from Cassini that will be released over the next several days capture each of the four Galilean satellites in their orbits around the giant planet. This true-color composite frame, made from narrow angle images taken on Dec. 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers (12.1 million miles). The image scale is 117 kilometers (73 miles) per pixel. The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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This image taken by NASA's Cassini spacecraft on Dec. 1, 2000, shows details of Jupiter's Great Red Spot and other features that were not visible in images taken earlier, when Cassini was farther from Jupiter. The picture is a color composite, with enhanced contrast, taken from a distance of 28.6 million kilometers (17.8 million miles). It has a resolution of 170 kilometers (106 miles) per pixel. Jupiter's closest large moon, Io, is visible at left. The edges of the Red Spot are cloudier with ammonia haze than the spot's center is. The filamentary structure in the center appears to spiral outward toward the edge. NASA's Galileo spacecraft has previously observed the outer edges of the Red Spot to be rotating rapidly counterclockwise, while the inner portion was rotating weakly in the opposite direction. Whether the same is true now will be answered as Cassini gets closer to Jupiter and interior cloud features become sharper. Cassini will make its closest approach to Jupiter, at a distance of about 10 million kilometers (6 million miles), on Dec. 30, 2000. The Red Spot region has changed in one notable way over the years: In images from NASA's Voyager and Galileo spacecraft, the area surrounding the Red Spot is dark, indicating relatively cloud-free conditions. Now, some bright white ammonia clouds have filled in the clearings. This appears to be part of a general brightening of Jupiter's cloud features during the past two decades. Jupiter has four large moons and an array of tiny ones. In this picture, Io is visible. The white and reddish colors on Io's surface are due to the presence of different sulfurous materials while the black areas are due to silicate rocks. Like the other large moons, Io always keeps the same hemisphere facing Jupiter, called the sub-Jupiter hemisphere. The opposite side, much of which we see here, is the anti-Jupiter hemisphere. Io has more than 100 active volcanoes spewing very hot lava and giant plumes of gas and dust. Its biggest plume, Pele, is near the bottom left edge of Io's disk as seen here. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona. For higher resolution, click here. |
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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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Jupiter Lightning Storms, Day and Night January 23, 2001 Images taken of Jupiter¿s day and night sides by NASA's Cassini spacecraft on Jan. 1, 2001 show that storms visible on the day side are the sources of visible lightning when viewed on the night side. The two day-side occurrences of high clouds, in the upper and lower parts of the image, are coincident with lightning storms seen on the dark side. The storms occur at 34.5 degrees and 23.5 degrees North latitude, within one degree of the latitudes at which similar lightning features were detected by the Galileo spacecraft. The storms' longitudinal separation changes from one image to the next because the winds carrying them blow at different speeds at the two latitudes. The images have been enhanced in contrast. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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The solar system's largest moon, Ganymede, is captured here alongside the planet Jupiter in a color picture taken by NASA's Cassini spacecraft on Dec. 3, 2000. Ganymede is larger than the planets Mercury and Pluto and Saturn's largest moon, Titan. Both Ganymede and Titan have greater surface area than the entire Eurasian continent on our planet. Cassini was 26.5 million kilometers (16.5 million miles) from Ganymede when this image was taken. The smallest visible features are about 160 kilometers (about 100 miles) across. The bright area near the south (bottom) of Ganymede is Osiris, a large, relatively new crater surrounded by bright icy material ejected by the impact which created it. Elsewhere, Ganymede displays dark terrains that NASA's Voyager and Galileo spacecraft have shown to be old and heavily cratered. The brighter terrains are younger and laced by grooves. Various kinds of grooved terrains have been seen on many icy moons in the solar system. These are believed to be the surface expressions of warm, pristine, water-rich materials that moved to the surface and froze. Ganymede has proven to be a fascinating world, the only moon known to have a magnetosphere, or magnetic environment, produced by a convecting metal core. The interaction of Ganymede's and Jupiter's magnetospheres may produce dazzling variations in the auroral glows in Ganymede's tenuous atmosphere of oxygen. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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This color image of Jupiter was taken by the camera onboard NASA's Cassini spacecraft when it was 81.3 million kilometers (50.5 million miles) from the planet. It is composed of images taken in the blue, green, and red regions of the spectrum and is therefore close to the true color of Jupiter that one would see through an Earth-based telescope. The image is remarkably similar to images taken by NASA's Voyager 1 and 2 spacecraft more than 21 years ago, illustrating the stability of Jupiter's weather patterns. The parallel dark and bright bands and many other large-scale features are quasi-permanent structures that survive despite the intense small-scale activity ongoing in the atmosphere. The longevity of the large-scale features is an intrinsic property of the atmospheric flows on a gaseous planet such as Jupiter, with no solid surface. Smaller features, such as those in the dark bands north and south of the equator, are observed to form and disappear in a few days. Everything visible on the planet is a cloud. Unlike Earth, where only water condenses to form clouds, Jupiter has several cloud-forming substances in its atmosphere. The updrafts and downdrafts bring different mixtures of these substances up from below, leading to clouds of different colors. The bluish features just north of the equator are regions of reduced cloud cover, similar to the place where the Galileo atmospheric probe entered in 1995. They are called "hot spots" because the reduced cloud cover allows heat to escape from warmer, deeper levels in the atmosphere. Jupiter's moon Europa is seen at the right, casting a shadow on the planet. Scientists believe Europa holds promise of a liquid ocean beneath its surface. 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, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. Credit: NASA/JPL/University of Arizona, (PIA02972) For higher resolution, click here. |
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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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One moment in an ancient, orbital dance is caught in this color picture taken by NASA's Cassini spacecraft on Dec. 7, 2000, just as two of Jupiter's four major moons, Europa and Callisto, were nearly perfectly aligned with each other and the center of the planet. The distances are deceiving. Europa, seen against Jupiter, is 600,000 kilometers (370,000 miles) above the planet's cloud tops. Callisto, at lower left, is nearly three times that distance from the cloud tops. Europa is a bit smaller than Earth's Moon and has one of the brightest surfaces in the solar system. Callisto is 50 percent bigger -- roughly the size of Saturn's largest satellite, Titan -- and three times darker than Europa. Its brightness had to be enhanced in this picture, relative Europa's and Jupiter's, in order for Callisto to be seen in this image. Europa and Callisto have had very different geologic histories but share some surprising similarities, such as surfaces rich in ice. Callisto has apparently not undergone major internal compositional stratification, but Europa's interior has differentiated into a rocky core and an outer layer of nearly pure ice. Callisto's ancient surface is completely covered by large impact craters: The brightest features seen on Callisto in this image were discovered by the Voyager spacecraft in 1979 to be bright craters, like those on our Moon. In contrast, Europa's young surface is covered by a wild tapestry of ridges, chaotic terrain and only a handful of large craters. Recent data from the magnetometer carried by the Galileo spacecraft, which has been in orbit around Jupiter since 1995, indicate the presence of conducting fluid, most likely salty water, inside both Callisto and Europa. Scientists are eager to discover whether the surface of Saturn's Titan resembles that of Callisto or Europa, or whether it is entirely different, when Cassini finally reaches its destination in 2004. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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Images from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole. Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure. The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The top two images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths. The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter bright near the pole. The equatorial band is also very bright in the strong 890-nm image and to a lesser extent in the 727 band (middle image) but is subdued in the weak 619-nm image at the top. These are high, thin, haze layers that are nearly transparent at wavelengths outside the methane absorption bands. Another prominent feature is the Great Red Spot. About a third of it appears at the right-hand edge of the frame. It is a bright feature in methane absorption because it has extensive cloud cover reaching to high altitude. A wisp of high thin cloud can be seen trailing off its western rim in the middle and lowest images. Features mentioned above have been seen from ground-based telescopes, from NASA's Hubble Space Telescope and from NASA's Galileo spacecraft. This is the first high-resolution image in all three methane bands, and a comparison of all three reveals some interesting features. Chief among these is the very dark patch seen in the top (weak methane) image near the top-middle of the frame. It is almost invisible in the bottom image and it appears to be composed of strands of bright clouds in the middle image. This is a region similar to the hot spot, where the Galileo Probe entered Jupiter's atmosphere in 1995. These images indicate that cloud cover is present at the higher altitudes but absent from the lower altitudes. This is also what the Galileo Probe found when it entered Jupiter's atmosphere. To the northwest (above and to the left) of the dark feature is a small cloud that is bright in the 619-nm (top) image but has no contrast at the other wavelengths. This is the signature expected for a thick water cloud. Another feature seen only in the weak-methane (top image) ratio is a dark ring near the center of the image. This feature is probably a counter-clockwise rotating, upwelling core surrounded by a sinking perimeter with diminished cloudiness. The fact that it is seen only in the weak methane ratio indicates the effects of a lower-level circulation that does not penetrated to the upper ammonia cloud level and may be confined to the deeper water cloud. The opposite behavior is evident in an oval storm that appears dark in the middle and bottom images but is absent in the weak, 619-nm image. It is located to the southwest of the Great Red Spot. Further to the west at slightly more northerly latitudes are a series of small spots that are dark at all wavelengths. These and a myriad of other contrast features at many latitudes reveal much about Jupiter's complicated cloud structure and meteorology. 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, Washington, D.C. Credit: NASA/JPL/University of Arizona For higher resolution, click here. |
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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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Download the free RealPlayer 8 Basic View RealPlayer video in its own window Inner Radiation Belts of Jupiter February 27, 2002 Details in radiation belts close to Jupiter are mapped from measurements that NASA's Cassini spacecraft made of radio emission from high-energy electrons moving at nearly the speed of light within the belts. The three views show the belts at different points in Jupiter's 10-hour rotation. A picture of Jupiter is superimposed to show the size of the belts relative to the planet. Cassini's radar instrument, operating in a listen-only mode, measured the strength of microwave radio emissions at a frequency of 13.8 gigahertz (13.8 billion cycles per second or 2.2 centimeter wavelength). The results indicate the region near Jupiter is one of the harshest radiation environments in the solar system. From Earth-based radio telescopes, the telltale radio emissions would be swamped out by heat-generated radio emissions from Jupiter's atmosphere, but Cassini was close enough to Jupiter in January 2001 to differentiate between the emissions from the radiation belts and those from the atmosphere. The belts appear to wobble as the planet turns because they are controlled by Jupiter's magnetic field, which is tilted in relation to the planet's poles. For more information about the Saturn-bound Cassini spacecraft and its observations of Jupiter, see the Cassini home page, http://saturn.jpl.nasa.gov. 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, Washington, D.C. Credit: NASA/JPL 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. For higher resolution, click here. |
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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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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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Jupiter's Magnetosphere Made Visible February 27, 2002 The vast magnetosphere of charged particles whirling around Jupiter, normally invisible, can be imaged by a new type of instrument aboard NASA's Cassini spacecraft and is seen here. Three features are sketched in for context: a black circle showing the size of Jupiter, lines of Jupiter's magnetic field, and a cross-section of the Io torus, a doughnut-shaped ring of charged particles that originate from volcanic eruptions on Jupiter's moon Io and circle Jupiter at about the orbit of Io. Jupiter's magnetosphere is the largest object in the solar system. If it glowed in wavelengths visible to the eye, it would appear two to three times the size of the Sun or Moon to viewers on Earth. Cassini's ion and neutral camera detects neutral atoms expelled from the magnetosphere, deriving information about their source. This image was taken shortly after Cassini's closest approach to Jupiter, about 10 million kilometers (6 million miles) from the planet on Dec. 30, 2000. For more information about the Saturn-bound spacecraft and its observations of Jupiter, see the Cassini home page, http://saturn.jpl.nasa.gov. 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, Washington, D.C. Credit: NASA/JPL/Johns Hopkins University Applied Physics Laboratory 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. For higher resolution, click here. |
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Cassini's Best Maps of Jupit
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This map is part of a group release of cylindrical and polar stereographic projections of Jupiter. |
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This map is part of a group release of cylindrical and polar stereographic projections of Jupiter. For the other maps see PIA07782 and PIA07784. (Related thumbnail images available here.) These color maps of Jupiter were constructed from images taken by the narrow-angle camera onboard NASA's Cassini spacecraft on Dec. 11 and 12, 2000, as the spacecraft neared Jupiter during its flyby of the giant planet. Cassini was on its way to Saturn. They are the most detailed global color maps of Jupiter ever produced. The smallest visible features are about 120 kilometers (75 miles) across. The maps are composed of 36 images: a pair of images covering Jupiter's northern and southern hemispheres was acquired in two colors every hour for nine hours as Jupiter rotated beneath the spacecraft. Although the raw images are in just two colors, 750 nanometers (near-infrared) and 451 nanometers (blue), the map's colors are close to those the human eye would see when gazing at Jupiter. The maps show a variety of colorful cloud features, including parallel reddish-brown and white bands, the Great Red Spot, multi-lobed chaotic regions, white ovals and many small vortices. Many clouds appear in streaks and waves due to continual stretching and folding by Jupiter's winds and turbulence. The bluish-gray features along the north edge of the central bright band are equatorial "hot spots," meteorological systems such as the one entered by NASA's Galileo probe. Small bright spots within the orange band north of the equator are lightning-bearing thunderstorms. The polar regions are less clearly visible because Cassini viewed them at an angle and through thicker atmospheric haze (such as the whitish material in the south polar map -- see PIA07784). Pixels in the rectangular map cover equal increments of planetocentric latitude (which is measured relative to the center of the planet) and longitude, and extend to 180 degrees of latitude and 360 degrees of longitude. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . *Credit:* NASA/JPL/Space Science Institute |
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March 27, 2006 |
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Cassini's Best Maps of Jupit
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This map is part of a group release of cylindrical and polar stereographic projections of Jupiter. |
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This map is part of a group release of cylindrical and polar stereographic projections of Jupiter. For the other maps see PIA07782 and PIA07784. (Related thumbnail images available here.) These color maps of Jupiter were constructed from images taken by the narrow-angle camera onboard NASA's Cassini spacecraft on Dec. 11 and 12, 2000, as the spacecraft neared Jupiter during its flyby of the giant planet. Cassini was on its way to Saturn. They are the most detailed global color maps of Jupiter ever produced. The smallest visible features are about 120 kilometers (75 miles) across. The maps are composed of 36 images: a pair of images covering Jupiter's northern and southern hemispheres was acquired in two colors every hour for nine hours as Jupiter rotated beneath the spacecraft. Although the raw images are in just two colors, 750 nanometers (near-infrared) and 451 nanometers (blue), the map's colors are close to those the human eye would see when gazing at Jupiter. The maps show a variety of colorful cloud features, including parallel reddish-brown and white bands, the Great Red Spot, multi-lobed chaotic regions, white ovals and many small vortices. Many clouds appear in streaks and waves due to continual stretching and folding by Jupiter's winds and turbulence. The bluish-gray features along the north edge of the central bright band are equatorial "hot spots," meteorological systems such as the one entered by NASA's Galileo probe. Small bright spots within the orange band north of the equator are lightning-bearing thunderstorms. The polar regions are less clearly visible because Cassini viewed them at an angle and through thicker atmospheric haze (such as the whitish material in the south polar map -- see PIA07784). Pixels in the rectangular map cover equal increments of planetocentric latitude (which is measured relative to the center of the planet) and longitude, and extend to 180 degrees of latitude and 360 degrees of longitude. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . *Credit:* NASA/JPL/Space Science Institute |
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March 27, 2006 |
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