Narrow Search
 
 
Advanced Search

Browse All : Near Infrared Mapping Spectrometer (NIMS) of Jet Propulsion Laboratory from 1999

Printer Friendly
1-13 of 13
     
     
A New Hot Spot on Northern I …
PIA03602
Jupiter
Near Infrared Mapping Spectr …
Title A New Hot Spot on Northern Io
Original Caption Released with Image NASA's Galileo spacecraft has returned infrared imagery of a new hot spot on Jupiter's moon Io that was the source of a towering plume in August 2001, indicating a sulfur-dioxide concentration that may have been fallout from the plume. Galileo's near-infrared mapping spectrometer captured the image on the left during an Oct. 16, 2001 flyby of Io. Coloring indicates the intensity of glowing at a wavelength of 4.1 microns. Yellow, red, and white represent high temperatures. Black is where the near-infrared glow was so intense the image was saturated. Greens and blues are cold. The visible-light image on the right was obtained by Galileo's camera in 1999, before any volcanic activity was seen at this site. The first sign of activity came in August 2001, when Galileo detected an infrared hot spot and the tallest volcanic plume ever seen at Io. The dark blue band north of the hot spot in the new infrared image represents a concentration of sulfur-dioxide, which has a strong signature in the infrared. The sulfur-dioxide is thought to be from the fallout of the plume. The image shows high temperatures corresponding to yellow flows in the center of the visible-light image, and from a small caldera at the 8 o'lock position. 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. Additional information about Galileo and its discoveries is available on the Galileo mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
NIMS Observes the Structure …
PIA01224
Sol (our sun)
Near Infrared Mapping Spectr …
Title NIMS Observes the Structure and Composition of Jupiter's Clouds
Original Caption Released with Image 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://galileo.jpl.nasa.gov., With the NIMS instrument high quality observations are being obtained from all parts of Jupiter. The images in the upper panel are taken at a wavelength of 4.8 microns. At this wavelength thermal radiation from about 100 km deep below the visible cloud deck is escaping, allowing us to study the deep atmospheric region. The overlying cloud deck absorbs a part of the radiation, but there are places where it is thin and more radiation can escape. These are called hot spot regions. Many hotspots regions occur in a zone between the equator and 15 degrees north latitude, the North Equatorial Belt (NEB), but thermal radiation is seen from much of the planet. The uniqueness of NIMS is that it is capable of observing the same spatial region at a maximum of 408 different wavelengths between 0.7 and 5.2 micron simultaneously. Every picture element (pixel) contains a spectrum of up to 408 wavelengths. The gases that compose the atmosphere leave there traces in the spectra. In this particular case, 48 wavelengths were available between 4.6 and 5.2 micron, and we see spectral signatures of water, ammonia, and phosphine. Also, the total amount of radiation is determined by the amount of overlying cloud, characterized by the cloud opacity. By means of model calculations, we can determine the amount of water and the cloud opacity for each individual spectrum. The amount ammonia and phosphine is more difficult to obtain because its influence on the spectra is weaker. The results of these calculations are shown in the form of maps in the next two panels. With NIMS, we can now have a detailed look at the spatial distribution of the water and ammonia amounts and the cloud opacity in the atmosphere. Not all the pixels from the observations have good spectra, so for some data points no reliable determination of the water and cloud opacity could be made. We find that the atmosphere is extremely dry in, and close to, the hot spot, with relative humidities between 0.02 % and 10 %, with the dryest places being inside the hot spot. This corroborates the in-situ Galileo Entry Probe measurements. The Probe entered the atmosphere, on December 5 1995, in a hot spot region. Whereas the Probe obtained only a very localized snapshot, with NIMS we can do observations of larger areas and over longer periods. The spatial distribution of water is more complex than expected. More detailed investigations will be necessary to fully understand these results. Future studies will also allow a better understanding of the dynamics of the Jovian atmosphere, since the spatial distribution of water is thought to be a tracer for atmospheric motions under the cloud deck. NIMS will continue to provide excellent and unique data during the Galileo Europa Mission, planned to last until December 1999. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's
Europa: Sea Salts or Battery …
PIA02529
Jupiter
Near Infrared Mapping Spectr …
Title Europa: Sea Salts or Battery Acid
Original Caption Released with Image 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 European "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). Click on this thumbnail image above to view the above image in a Global context. 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 [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Europa: Sea Salts or Battery …
PIA02529
Jupiter
Near Infrared Mapping Spectr …
Title Europa: Sea Salts or Battery Acid
Original Caption Released with Image 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 European "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). Click on this thumbnail image above to view the above image in a Global context. 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 [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Galileo's Near-Infrared Mapp …
PIA02509
Jupiter
Near Infrared Mapping Spectr …
Title Galileo's Near-Infrared Mapping Spectrometer Detects Active Lava Flows at Prometheus Volcano, Io
Original Caption Released with Image The active volcano Prometheus on Jupiter's moon Io was imaged by the near-infrared mapping spectrometer instrument onboard NASA's Galileo spacecraft during the close flyby of Io on October 10, 1999. The images were taken at a distance of about 15,000 kilometers (9,400 miles). The spectrometer can detect active volcanoes on Io by measuring their heat in the near-infrared wavelengths (just beyond the red end of human vision). It can also obtain information on the composition of materials on Io¹s surface using the same wavelengths. The image on the left, taken at an infrared wavelength, shows the different compositions of materials on the volcano. The dark material is thought to be silicate lava, and the white material is sulfur dioxide frost. Sulfur dioxide erupts out of this volcano as a plume and condenses into snow by the time it reaches the ground, forming a distinctive white ring around the volcano. The image on the right was taken at a longer infrared wavelength that shows heat coming out of the volcano. The hottest areas appear white and the coolest appear black. From this image, it is clear that there are two major "hot spots" (high-temperature areas) on this volcano. The hottest area (white spot on the left) corresponds to a location where images taken by Galileo's camera show a complex lava flow field. The cooler "hot spot" (green spot on the right) is located near where camera images show a newly-discovered volcanic caldera [ http://photojournal.jpl.nasa.gov/catalog/PIA02508 ]. The high temperatures at both hot spots are probably due to active lava flowing on the surface. Previous observations of the Prometheus region by the spectrometer, taken when the spacecraft was at much greater distances from Io, showed Prometheus to be a persistently active volcano. Temperatures calculated from spectrometer data areas high as about 800 degrees Celsius or 1,500 Fahrenheit), similar to those of cooling lava flows in Hawaii. The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at http://galileo.jpl.nasa.gov/ [ http://galileo.jpl.nasa.gov/ ] Background information and educational context for the images can be found athttp://galileo.jpl.nasa.gov/images/images.html [ http://galileo.jpl.nasa.gov/images/images.html ]
Galileo PPR temperature maps …
PIA02524
Jupiter
Title Galileo PPR temperature maps of Loki in October 1999
Original Caption Released with Image Like a terrestrial weather map, this map made by the photopolarimeter-radiometer onboard NASA's Galileo spacecraft shows how temperatures vary across the surface of Jupiter's moon Io. However, in this case the temperatures are due to volcanic activity, not weather. The maps show Io's most powerful volcano, Loki, which was in the throes of one of its periodic bright eruptions when the map was made during Galileo's close flyby of Io on October. The background to the temperature map is a Galileo image of Loki taken earlier in the Galileo mission. Loki's most prominent feature is the huge horseshoe-shaped dark caldera, 200 kilometers (120 miles) across. These observations reveal that most of the lava lake is at a remarkably uniform temperature, about -23 degrees C (-9 degrees F). This is chilly by Earth standards, but on Io, where most of the surface is colder than -145 degrees C (-230 degrees F), enormous amounts of volcanic heat are required to keep such a large area at this temperature. The uniform temperature, which was also seen by Galileo's Near Infrared Mapping Spectrometer, could be due to a uniformly thick frozen crust over a lake of molten lava, or to a series of old lava flows that have been cooling down for a year or two since they erupted. The southwestern corner of the caldera is much hotter the highest resolution photopolarimeter-radiometer observation shows peak temperatures of at least 126 degrees C (260 F). It is likely that this is the site of the new eruption that began in September, and that fresh lava erupting there will eventually spill out from this region to warm up the parts of the caldera to the east and north. 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 mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Prometheus silicates/sulfur …
PIA02543
Jupiter
Near Infrared Mapping Spectr …
Title Prometheus silicates/sulfur dioxide/NIMS
Original Caption Released with Image The Prometheus region of Jupiter's moon Io was imaged by the camera onboard NASA's Galileo spacecraft in July 1999 (A), and by the spacecraft's near-infrared mapping spectrometer during its October 10, 1999 flyby (B). The maps made from spectrometer data show the interplay between hot silicates on the surface and sulfur dioxide frost. Hot spots (active volcanoes) appear red in the spectrometer image (B), while sulfur dioxide frost appears blue. Hot spots known from prior observations are labeled 1(Prometheus), 5 (Camaxtli), 7 (Tupan) and 8 (Culann). Hot spots labeled 2,3, 4, and 6 were first discovered in this observation. The color bar scale in (B) represents radiance in units of solar irradiance/pi. The sulfur dioxide deposition ring around Prometheus is clearly seen in the center of the image, formed as sulfur dioxide from the currently active plume condenses away from the vent. Image (C) is a map of the relative band-depth of the sulfur dioxide absorption band that is detected by the spectrometer. Image (D) is a qualitative map of the distribution of sulfur dioxide frost on the surface. The color bar in (D) represents the fractional area covered by sulfur dioxide frost. The area shown in each panel is about 1,300 km (800 miles) across. The Jet Propulsion Laboratory, Pasadena, CA manages the 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 mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Loki Patera/NIMS
PIA02541
Jupiter
Near Infrared Mapping Spectr …
Title Loki Patera/NIMS
Original Caption Released with Image This image of Loki Patera on Jupiter's volcanic moon Io shows data taken by the near-infrared mapping spectrometer onboard NASA's Galileo spacecraft during its Io flyby on October 10, 1999, superimposed on a Galileo camera image 162 kilometers (100 miles) across. The spectrometer observation has been translated into two types of temperature maps. Image A represents brightness temperatures, which are calculated by assuming that each whole pixel is at a uniform temperature. This map shows that the dark caldera floor is warm, while the light-colored island in the middle of the caldera and the terrain outside the caldera are cool. The scale on the side gives the temperatures in degrees Kelvin (280Kelvins = 45 degrees Fahrenheit, warm compared to the temperature of Io's surface, which is about 122 Kelvin, or -240 Fahrenheit). Image B represents color temperatures, which are calculated assuming the areas emitting heat can be smaller than the area of a single pixel. This map shows that the hottest temperatures (up to 460 Kelvin or 370 F) are seen in a crack running through the center of the island. The maps indicate that the floor and crack on the caldera are filled with cooling lava flows, the youngest (and therefore hottest) lavas being those in the crack. These lavas are thought to be a few months old. The Jet Propulsion Laboratory, Pasadena, CA manages the 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 mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Culann Patera/NIMS
PIA02544
Jupiter
Near Infrared Mapping Spectr …
Title Culann Patera/NIMS
Original Caption Released with Image The Culann Patera volcano on Jupiter's moon Io was observed by the near-infrared mapping spectrometer instrument onboard NASA's Galileo spacecraft during its Io flyby on November 25, 1999. The instrument obtained spectral data over part of Culann. The spectra were made into a map of the relative amounts of sulfur dioxide frost, superimposed on an image taken by Galileo's camera in July 1999. In the map, white represents more sulfur dioxide. The image is about 340 kilometers (210 miles) across. The red deposits around Culann and many other volcanoes on Io are thought to be short-chain sulfur molecules (S3 and S4). The spectrometer data shows that the red deposits coincide with enhanced concentrations of sulfur dioxide frost. This is interpreted as being caused by a plume that produced both sulfur and sulfur dioxide, depositing both materials in the same locations. The Jet Propulsion Laboratory, Pasadena, CA manages the 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 mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Prometheus/NIMS
PIA02542
Jupiter
Near Infrared Mapping Spectr …
Title Prometheus/NIMS
Original Caption Released with Image Volcanic "hot spots" are seen in this color temperature map of the Prometheus volcano (A) on Jupiter's moon Io created with data obtained by the near-infrared mapping spectrometer onboard NASA's Galileo spacecraft during the flyby of Io on October 10, 1999. An image obtained by Galileo's onboard camera during an earlier orbit is also shown (B). The dark area in the camera image is a lava flow about 80 kilometers (50 miles) long. Two major hot areas are seen in the spectrometer data. The eastern hot spot(right) is located near the site of a plume observed by NASA's Voyager spacecraft in 1979. The cooler western hot spot (left) coincides with the location of the current plume. This temperature map supports the idea that the main vent of the volcano is on the eastern side, and that the plume is erupting from a "rootless vent," created as the hot lava flow interacted with sulfur dioxide snow. The Jet Propulsion Laboratory, Pasadena, CA manages the 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 mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Myriad of Hot Spots on Io
PIA02558
Jupiter
Near Infrared Mapping Spectr …
Title Myriad of Hot Spots on Io
Original Caption Released with Image Changes in the volcanoes on Jupiter's moon Io can be seen in these three views, taken by NASA's Galileo spacecraft during its three flybys of Io in October 1999, November 1999 and February 2000. All the images show the active volcanoes as bright yellow, corresponding to hot lava flows that appear glowing in infrared wavelengths. The three views were taken by the spacecraft's near-infrared mapping spectrometer instrument and show the comparison of a typical low-resolution observation to the high-resolution views. The regional observations taken during the recent Io flybys are superimposed on an image taken during Galileo in 1996. The Prometheus volcano is seen near the middle of all three images. Before the recent flybys, only Prometheus and three other volcanoes were known to be active in this region. After these and other high-resolution observations, scientists were able to detect 14 volcanoes in the same area. The fainter volcanoes (hot spots) show some significant changes over intervals of 1 to 3 months. The area shown by all three observations put together is about 2 million square kilometers (about 770,000 square miles) and covers about 5 percent of Io's surface. The Jet Propulsion Laboratory, Pasadena, Calif., manages the mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page athttp://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ]. Background information and educational context for the images can be found at http://galileo.jpl.nasa.gov/gallery/io.cfm [ http://galileo.jpl.nasa.gov/gallery/io.cfm ].
Io's Tvashtar Area in Infrar …
PIA02594
Jupiter
Near Infrared Mapping Spectr …
Title Io's Tvashtar Area in Infrared: Multiple Lava Flows
Original Caption Released with Image New and older lava flows clustered in the Tvashtar region of Jupiter's moon Io appear as hot spots in a temperature map from NASA's Galileo spacecraft. The multiple hot spots indicate continuing shifts in the location of Tvashtar's eruptions since the region's volcanic activity was first seen in December 1999. The temperature map (top) uses infrared observations made during Galileo's Aug. 6, 2001, flyby of Io. It is shown using landmarks from a February 2000 visible-light image (bottom) that Galileo's camera recorded of the Tvashtar area of bowl-like depressions in Io's northern hemisphere. The temperature map comes from Galileo's near-infrared mapping spectrometer. Tvashtar has been a very active region since December 1999, when Galileo detected a major eruption from the location marked A (See insert image below). The eruption from A was interpreted as a row of lava fountains. When Galileo flew by Io again in February 2000, the eruption had shifted to the location marked B, where a lava flow shaped like a dolphin's tail is seen. The temperature map shows that volcanic activity is present at many locations in this region. The highest temperatures are found in the three locations marked x, where new lavas may have recently come to the surface. Temperatures (in Kelvin) displayed in the color bar are lower limits. (The range in Fahrenheit is from 460 degrees below zero to 530 degrees above zero.) Each picture element averages the characteristics of an area about 2 kilometers (1.2 miles) across, smaller patches may be hundreds of degrees higher. The Galileo camera did not obtain a visible-light image of the Tvashtar region during the August 2001 flyby. Based on the locations of the hottest materials detected by Galileo's near-infrared mapping spectrometer, volcanologists expect that significant surface changes have occurred.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. Additional information about the spacecraft and its discoveries is available on the Galileo home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ].
Io's Tvashtar Area in Infrar …
PIA02594
Jupiter
Near Infrared Mapping Spectr …
Title Io's Tvashtar Area in Infrared: Multiple Lava Flows
Original Caption Released with Image New and older lava flows clustered in the Tvashtar region of Jupiter's moon Io appear as hot spots in a temperature map from NASA's Galileo spacecraft. The multiple hot spots indicate continuing shifts in the location of Tvashtar's eruptions since the region's volcanic activity was first seen in December 1999. The temperature map (top) uses infrared observations made during Galileo's Aug. 6, 2001, flyby of Io. It is shown using landmarks from a February 2000 visible-light image (bottom) that Galileo's camera recorded of the Tvashtar area of bowl-like depressions in Io's northern hemisphere. The temperature map comes from Galileo's near-infrared mapping spectrometer. Tvashtar has been a very active region since December 1999, when Galileo detected a major eruption from the location marked A (See insert image below). The eruption from A was interpreted as a row of lava fountains. When Galileo flew by Io again in February 2000, the eruption had shifted to the location marked B, where a lava flow shaped like a dolphin's tail is seen. The temperature map shows that volcanic activity is present at many locations in this region. The highest temperatures are found in the three locations marked x, where new lavas may have recently come to the surface. Temperatures (in Kelvin) displayed in the color bar are lower limits. (The range in Fahrenheit is from 460 degrees below zero to 530 degrees above zero.) Each picture element averages the characteristics of an area about 2 kilometers (1.2 miles) across, smaller patches may be hundreds of degrees higher. The Galileo camera did not obtain a visible-light image of the Tvashtar region during the August 2001 flyby. Based on the locations of the hottest materials detected by Galileo's near-infrared mapping spectrometer, volcanologists expect that significant surface changes have occurred.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. Additional information about the spacecraft and its discoveries is available on the Galileo home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ].
1-13 of 13