Narrow Search
 
 
Advanced Search

Browse All : Advanced Communication Technology Satellite (ACTS) and Earth of Jet Propulsion Laboratory (JPL)

Printer Friendly
1-15 of 15
     
     
Weddell Sea, Antarctica L, C …
This Spaceborne Imaging Rada …
10/5/94
Date 10/5/94
Description This Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar color composite shows a portion of the Weddell Sea, which is adjacent to the continent of Antarctica. The image shows extensive coverage of first-year sea ice mixtures and patches of open water inside the ice margin. The image covers a 100 kilometer by 30 kilometer (62 mile by 18.5 mile) region of the southern ocean, centered at approximately 57 degrees south latitude and 3 degrees east longitude, which was acquired on October 3, 1994. Data used to create this image were obtained using the L-band (horizontally transmitted and vertically received) in red, the L-band (horizontally transmitted and received) in green, and the C-band (horizontally transmitted and received) in blue. The sea ice, which appears rust-brown in the image, is composed of loosely packed floes from approximately 1 meter to 2 meters (3 feet to 6.5 feet) thick and ranging from 1 meter to 20 meters (3 feet to 65.5 feet) in diameter. Large patches of open water, shown as turquoise blue, are scattered throughout the area, which is typical for ice margins experiencing off-ice winds. The thin, well-organized lines clearly visible in the ice pack are caused by radar energy reflected by floes riding the crest of ocean swells. The wispy, black features seen throughout the image represent areas where new ice is forming. Sea ice, because it acts as an insulator, reduces the loss of heat between the relatively warm ocean and cold atmosphere. This interaction is an important component of the global climate system. Because of the unique combination of winds, currents and temperatures found in this region, ice can extend many hundreds of kilometers north of Antarctica each winter, which classifies the Weddell Sea as one of nature's greatest ice-making engines. During the formation of sea ice, great quantities of salt are expelled from the frozen water. The salt increases the density of the upper layer of sea water, which then sinks to great depths. Oceanographers believe this process forms most of the oceans' deep water. Sea ice covering all of the southern oceans, including the Weddell Sea, typically reaches its most northerly extent in about September. As periods of daylight become gradually longer in the Southern Hemisphere, ice formation stops and the ice edge retreats southward. By February, most of the sea ice surrounding Antarctica disappears. Imaging radar is extremely useful for studying the polar regions because of the long periods of darkness and extensive cloud cover. The multiple frequencies of the SIR-C/X-SAR instruments allow further study into ways of improving the separation of the various thickness ranges of sea ice, which are vital to understanding the heat balance in the ice, ocean and atmospheric system. ----- Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves, allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by NASA's Jet Propulsion Laboratory. X-SAR was developed by the Dornier and Alenia Spazio companies for the German space agency, Deutsche Agentur fuer Raumfahrtangelegenheiten (DARA), and the Italian space agency, Agenzia Spaziale Italiana (ASI), with the Deutsche Forschungsanstalt fuer Luft und Raumfahrt e.V.(DLR), the major partner in science, operations and data processing of X-SAR.
Distance to Dark Bodies
Title Distance to Dark Bodies
Description Using the unique orbit of NASA's Spitzer Space Telescope and a depth-perceiving trick called parallax, astronomers have determined the distance to an invisible Milky Way object called OGLE-2005-SMC-001. This artist's concept illustrates how this trick works: different views from both Spitzer and telescopes on Earth are combined to give depth perception. Our Milky Way galaxy is heavier than it looks, and scientists use the term "dark matter" to describe all the "heavy stuff" in the universe that seems to be present but invisible to our telescopes. While much of this dark matter is likely made up of exotic materials, different from the ordinary particles that make up the world around us, some may consist of dark celestial bodies -- like planets, black holes, or failed stars -- that do not produce light or are too faint to detect from Earth. OGLE-2005-SMC-001 is one of these dark celestial bodies. Although astronomers cannot see a dark body, they can sense its presence from the way light acts around it. When a dark body like OGLE-2005-SMC-001 passes in front of a bright star, its gravity causes the background starlight to bend and brighten, a process called gravitational microlensing. When the observing telescope, dark body, and star system are closely aligned, the microlensing event reaches maximum, or peak, brightness. A team of astronomers first sensed OGLE-2005-SMC-001's presence when it passed in front of a star in a neighboring satellite galaxy called the Small Magellanic Cloud. In this artist's rendering, the satellite galaxy is depicted as the fuzzy structure sitting to the left of Earth. Once they detected this microlensing event, the scientists used Spitzer and the principle of parallax to figure out its distance. Humans naturally use parallax to determine distance. Each eye sees the position of an object differently. The brain takes each eye's perspective and instantaneously calculates how far away the object is. To determine OGLE-2005-SMC-001's distance, astronomers measured the microlensing event over several months with both Spitzer in space and the Earth-based telescopes. Careful analysis of the data revealed the time of the peak brightness differed slightly between the two locations. Because astronomers knew the exact distance between Earth and Spitzer and the time lag between the peak-observed brightness, they could determine OGLE-2005-SMC-001's speed. Using trigonometric equations and graphs to do the "brain's" job, scientists then inferred the dark body's location to be in the outer portion, or halo, of our galaxy. The picture of the Small Magellanic Cloud in this concept is a two-color image from two Digitized Sky Survey 2 observations The Digitized Sky Survey is based at the Space Telescope Science Institute in Baltimore, Md.
Planet Temperatures
title Planet Temperatures
description In general, the surface temperature of the planets decreases with increasing distance from the Sun. Venus is an exception because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead (3280C). Mercury rotates slowly and has a thin atmosphere, and consequently, the nightside temperature can be more than 5000C lower than the dayside temperature shown on the diagram. Temperatures for the gas giants (Jupiter, Saturn, Uranus, and Neptune) are shown at a level in the atmosphere equal in pressure to sea level on Earth. Temperatures are in both Fahrenheit and Celsius, and the planets are not shown to scale. *Image Credit*: Lunar and Planetary Institute
Breakup of the World's Large …
Title Breakup of the World's Largest Iceberg
Description Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green, and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60 degree forward-viewing, nadir, and 60 degree backward-viewing cameras are displayed as red, green, and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ]. Text by Clare Averill (Raytheon/JPL).
Breakup of the World's Large …
Title Breakup of the World's Largest Iceberg
Description Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green, and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60 degree forward-viewing, nadir, and 60 degree backward-viewing cameras are displayed as red, green, and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ]. Text by Clare Averill (Raytheon/JPL).
Distance to Dark Bodies
PIA09563
Title Distance to Dark Bodies
Original Caption Released with Image Using the unique orbit of NASA's Spitzer Space Telescope and a depth-perceiving trick called parallax, astronomers have determined the distance to an invisible Milky Way object called OGLE-2005-SMC-001. This artist's concept illustrates how this trick works: different views from both Spitzer and telescopes on Earth are combined to give depth perception. Our Milky Way galaxy is heavier than it looks, and scientists use the term "dark matter" to describe all the "heavy stuff" in the universe that seems to be present but invisible to our telescopes. While much of this dark matter is likely made up of exotic materials, different from the ordinary particles that make up the world around us, some may consist of dark celestial bodies -- like planets, black holes, or failed stars -- that do not produce light or are too faint to detect from Earth. OGLE-2005-SMC-001 is one of these dark celestial bodies. Although astronomers cannot see a dark body, they can sense its presence from the way light acts around it. When a dark body like OGLE-2005-SMC-001 passes in front of a bright star, its gravity causes the background starlight to bend and brighten, a process called gravitational microlensing. When the observing telescope, dark body, and star system are closely aligned, the microlensing event reaches maximum, or peak, brightness. A team of astronomers first sensed OGLE-2005-SMC-001's presence when it passed in front of a star in a neighboring satellite galaxy called the Small Magellanic Cloud. In this artist's rendering, the satellite galaxy is depicted as the fuzzy structure sitting to the left of Earth. Once they detected this microlensing event, the scientists used Spitzer and the principle of parallax to figure out its distance. Humans naturally use parallax to determine distance. Each eye sees the distance of an object differently. The brain takes each eye's perspective and instantaneously calculates how far away the object is. To determine OGLE-2005-SMC-001's distance, astronomers measured the microlensing event over several months with both Spitzer in space and the Earth-based telescopes. Careful analysis of the data revealed the time of the peak brightness differed slightly between the two locations. Because astronomers knew the exact distance between Earth and Spitzer and the time lag between the peak-observed brightness, they could determine OGLE-2005-SMC-001's speed. Using trigonometric equations and graphs to do the "brain's" job, scientists then inferred the dark body's location to be in the outer portion, or halo, of our galaxy. The picture of the Small Magellanic Cloud in this concept is a two-color image from two Digitized Sky Survey 2 observations The Digitized Sky Survey is based at the Space Telescope Science Institute in Baltimore, Md.
TOPEX/El Niño Watch - La Niñ …
PIA01525
Sol (our sun)
Altimeter
Title TOPEX/El Niño Watch - La Niña Weakening, January 17, 1999
Original Caption Released with Image This image of the Pacific Ocean was produced using sea-surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on January 17, 1999, sea surface height is an indicator of the heat content of the ocean. This image shows that the unusual large-scale warming (shown here in red and white) in the northwest Pacific that was first observed by the satellite in November 1998 has increased in size and spread east to the central Pacific and south to the equator. The low sea level or cold pool of water along the equator, commonly referred to as La Niña (shown in purple), has weakened in size and heat content during the last several months. Although weakening, the La Niña pattern continues to exert a strong influence on the worldwide climate system. According to oceanographers, the cold La Niña water acts like a boulder in a stream, steering the planet's prevailing winds and changing the course of storms that are born over the ocean. Equally important to North America's winter weather is the very large area of unusually warm Western Pacific ocean. Although the appearance of this feature is not fully understood or anticipated, it is adding energy to the winter storms coming out of the North Pacific which is fueling the very volatile weather over the continental U.S. In this image, the white areas show the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal, in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions. The purple areas are 14 to 18 centimeters (6 to 7 inches) below normal and the blue areas are 5 to 13 centimeters (2 to 5 inches) below normal. For more information, please visit the TOPEX/Poseidon project web page at http://topex-www.jpl.nasa.gov
Breakup of the World's Large …
PIA04344
Sol (our sun)
Multi-angle Imaging SpectroR …
Title Breakup of the World's Largest Iceberg
Original Caption Released with Image Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60° forward-viewing, nadir, and 60° backward-viewing cameras are displayed as red, green and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.
SeaWinds - South Georgia Isl …
PIA02457
Sol (our sun)
SeaWinds Scatterometer
Title SeaWinds - South Georgia Island
Original Caption Released with Image Winds are blocked by an island mountain barrier that produces a long "shadow" of low winds on the downwind side of the island stretching for hundreds of kilometers (about 500 miles long) in this image produced from data from NASA's SeaWinds instrument on the QuikScat satellite. South Georgia Island, in the South Atlantic Ocean (approximately 1,500 kilometers, or miles, east of the Falkland/Malvinas Islands, is only 170 kilometers long (about 106 miles) and 30 kilometers (about 19 miles)wide, but contains 13 peaks exceeding 2,000 meters (more than 6,500 feet) in height. The island thus acts as a significant barrier to the surface winds in this forbidding part of the world oceans. Mountainous islands and steep coastal topography can modify the surface wind field for many hundreds of kilometers seaward. The detailed air-sea-land interaction processes involved are not well understood, largely because of a lack of accurate, high-resolution, extensive wind speed and direction measurements. The broad-swath, all-weather SeaWinds instrument on NASA's QuikScat satellite is providing unique measurements of ocean winds, revealing previously unknown wind patterns caused by island topography and allowing development of improved models for coastal ocean winds. This image shows QuikScat measurements of wind speed and direction during a single pass over South Georgia Island on September 13, 1999. The island itself is shown as black (for heights less than 750 meters(less than half a mile), green (for heights between 750 and 1,500 meters (less than half a mile to about one mile), and red (for regions greater than 1,500 meters, or about one mile in altitude). The white area surrounding the island represents the region where land contamination does not allow wind measurements to be made. The horizontal and vertical coordinates are in kilometers, with origin on the island at latitude 54.5 degrees south, longitude 30 degrees east. This large-scale view shows regions of high wind speed off both the eastern and western ends of islands, corresponding to "corner accelerations" as the winds stream by the steep island topography. The lowest wind speeds are seen to be in the lee of the highest island topography. NASA's Earth Science Enterprise is a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system. JPL is a division of the California Institute of Technology, Pasadena, CA.
Mars Researchers Rendezvous …
PIA03714
Sol (our sun)
Multi-angle Imaging SpectroR …
Title Mars Researchers Rendezvous on Remote Arctic Island
Original Caption Released with Image Devon Island is situated in an isolated part of Canada's Nunavut Territory, and is usually considered to be the largest uninhabited island in the world. However, each summer since 1999, researchers from NASA's Haughton-Mars Project and the Mars Society reside at this "polar desert" location to study the geologic and environmental characteristics of a site which is considered to be an excellent "Mars analog": a terrestrial location wherein specific conditions approximate environmental features reported on Mars. Base camps established amidst the rocks and rubble surrounding the Haughton impact crater enable researchers to conduct surveys designed to test the habitat, equipment and technology that may be deployed during a human mission to Mars. One of the many objectives of the project scientists is to understand the ice formations around the Haughton area, in the hopes that this might ultimately assist with the recognition of areas where ice can be found at shallow depth on Mars. These images of Devon Island from NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument provide contrasting views of the spectral and angular reflectance "signatures" of different surfaces within the region. The top panel is a natural color view created with data from the red, green and blue-bands of MISR's nadir (vertical-viewing) camera. The bottom panel is a false-color multiangular composite of the same area, utilizing red band data from MISR's 60-degree backward, nadir, and 60-degree forward-viewing cameras, displayed as red, green and blue, respectively. In this representation, colors highlight textural properties of elements within the scene, with blue tones indicating smooth surfaces (which preferentially forward scatter sunlight) and red hues indicating rougher surfaces (which preferentially backscatter). The angular reflectance "signature" of low clouds causes them to appear purple, and this visualization provides a unique way of distinguishing clouds from snow and ice. The data were captured on June 28, 2001, during the early part of the arctic summer, when sea ice becomes thinner and begins to move depending upon localized currents and winds. In winter the entire region is locked with several meters of nearly motionless sea ice, which acts as a thermodynamic barrier to the loss of heat from the comparatively warm ocean to the colder atmosphere. Summer melting of sea ice can be observed at the two large, dark regions of open water, one is present in the Jones Sound (near the top to the left of center), and another appears in the Wellington Channel (left-hand edge). A large crack caused by tidal heaving has broken the ice cover over the Parry Channel (lower right-hand corner). A substantial ice cap permanently occupies the easternmost third of the island (upper right). Surface features such as dendritic meltwater channels incised into the island's surface are apparent. The Haughton-Mars project site is located slightly to the left and above image, center, in an area which appears with relatively little surface ice, near the island's inner "elbow." The images were acquired during Terra orbit 8132 and cover an area of about 334 kilometers x 229 kilometers. They utilize data from blocks 27 to 31 within World Reference System-2 path 42. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.
Clouds and Ice of the Lamber …
PIA03734
Sol (our sun)
Multi-angle Imaging SpectroR …
Title Clouds and Ice of the Lambert-Amery System, East Antarctica
Original Caption Released with Image These views from the Multi-angle Imaging SpectroRadiometer (MISR) illustrate ice surface textures and cloud-top heights over the Amery Ice Shelf/Lambert Glacier system in East Antarctica on October 25, 2002. The left-hand panel is a natural-color view from MISR's downward-looking (nadir) camera. The center panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60° forward-viewing, nadir and 60° backward-viewing cameras are displayed as red, green and blue, respectively. With this display technique, surfaces which predominantly exhibit backward-scattering (generally rough surfaces) appear red/orange, while surfaces which predominantly exhibit forward-scattering (generally smooth surfaces) appear blue. Textural variation for both the grounded and sea ice are apparent. The red/orange pixels in the lower portion of the image correspond with a rough and crevassed region near the grounding zone, that is, the area where the Lambert and four other smaller glaciers merge and the ice starts to float as it forms the Amery Ice Shelf. In the natural-color view, this rough ice is spectrally blue in color. Clouds exhibit both forward and backward-scattering properties in the middle panel and thus appear purple, in distinct contrast with the underlying ice and snow. An additional multi-angular technique for differentiating clouds from ice is shown in the right-hand panel, which is a stereoscopically derived height field retrieved using automated pattern recognition involving data from multiple MISR cameras. Areas exhibiting insufficient spatial contrast for stereoscopic retrieval are shown in dark gray. Clouds are apparent as a result of their heights above the surface terrain. Polar clouds are an important factor in weather and climate. Inadequate characterization of cloud properties is currently responsible for large uncertainties in climate prediction models. Identification of polar clouds, mapping of their distributions, and retrieval of their heights provide information that will help to reduce this uncertainty. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 15171. The panels cover an area of 380 kilometers x 984 kilometers, and utilize data from blocks 145 to 151 within World Reference System-2 path 127. MISR was built and is managed by NASA's Jet Propulsion Laboratory,Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center,Greenbelt, MD. JPL is a division of the California Institute of Technology.
Changing Lightning Storms on …
PIA01636
Sol (our sun)
Solid-State Imaging
Title Changing Lightning Storms on Jupiter
Original Caption Released with Image This view shows lightning storms in three different locations (panels 1, 2, and 3) on Jupiter's night side. Each panel shows multiple lightning strikes, coming from different parts of the same storm. The lightning originates in Jupiter's water cloud, which is 50 to 75 kilometers (30 to 45 miles) below the ammonia cloud. The latter acts as a translucent screen, diffusing the light over an area comparable to the depth. The individual strikes are unresolved in these images, which have a resolution of 133 kilometers (80 miles) per picture element. The brightest strikes emit as much light energy as 30 million 100-watt light bulbs burning for one second, which makes the strikes hundreds of times brighter than lightning on Earth. The bottom row shows the same three storms as the top row but the bottom-row images were taken two minutes later. The images were taken in the clear filter with an exposure time of 90 seconds. Clouds, illuminated by light reflected off Jupiter's moon Io, can be seen in the background. Moonlight on Jupiter is 100,000 times fainter than sunlight, and the lightning flashes would be undetectable on the day side of the planet. North is at the top of the picture. The planetocentric latitudes and west longitudes (in degrees) of the storms in panels 1 through 3 are (34.4, 16.1), (23.4, 27.6), and (8.6, 15.6), respectively. The panels are 8,000 kilometers (5,000 miles) on a side. The images in the top row were taken on October 6, 1997 at Universal Times (in hours:minutes:seconds), of 00:15:01, 00:17:03, and 00:17:03, respectively, by the solid state imaging camera system onboard NASA's Galileo spacecraft. Distance from the planet to the spacecraft was 6.62 million kilometers (4.1 million miles). JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ] . Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo [ http://www.jpl.nasa.gov/galileo/sepo ] .
Jovian Lightning and the Day …
PIA01638
Sol (our sun)
Solid-State Imaging
Title Jovian Lightning and the Daytime Storm
Original Caption Released with Image This picture highlights a convective storm (left panel) and the associated lightning (right panels) in Jupiter's atmosphere. The left image shows the dayside view. The right images show the area highlighted (box) in the dayside view as it appeared 110 minutes later during the night. Multiple lightning strikes are visible in the night side images, which were taken 3 minutes and 38 seconds apart. The bright, cloudy area in the dayside view is similar in appearance to a region of upwelling in Earth's atmosphere. The dark, clear region to the west (left) appears similar to a region of downwelling in Earth's atmosphere. The presence of lightning confirms that this is a site of moist convection. The lightning originates below the visible ammonia cloud, which acts as a translucent screen, diffusing the light over a wider area. This apparent width can be used to infer the depth of approximately 75 kilometers (46 miles). This figure is consistent with the hypothesis that lightning originates in the Jovian water cloud at about 75 kilometers (46 miles) depth. To show details of the lightning, the nightside images have been expanded by a factor of two relative to the dayside image. The latitude and longitude scale is shown around the left panel. On Jupiter, one degree of latitude spans a distance of 1,200 kilometers (744 miles), so the highlighted area is approximately 2,400 kilometers (1,488 miles) on a side. The resolution is 23 kilometers (14 miles) per picture element. The dayside image was taken through the 727 nanometer filter with an exposure of 0.529 seconds at 23:03:03 Universal Time on November 7, 1997. The upper night side image was taken through the red filter with an exposure of 166.9 seconds in gain state 1 at 00:49:590 Universal Time on November 8, 1997. The bottom night side image was taken through the red filter with an exposure of 38.9 seconds in gain state 2 at 00:53:37 Universal Time on November 8, 1997. The signal to noise ratio is greater in the lower night side image because the gain state is higher. The images were taken by the solid state imaging camera system on NASA's Galileo spacecraft at a range of 1.1 million kilometers (680,000 miles). JPL manages the Galileo mission for NASA's Office of Space Science, Washington, DC. This image and other images and data received from Galileo are posted on the World Wide Web on the Galileo mission home page at http://galileo.jpl.nasa.gov [ http://galileo.jpl.nasa.gov ] . Background information and educational context for the images can be found at http://www.jpl.nas a.gov/galileo/sepo [ http://www.jpl.nasa.gov/galileo/sepo ].
Candor Chasma
PIA03838
Sol (our sun)
Thermal Emission Imaging Sys …
Title Candor Chasma
Original Caption Released with Image (Released 27 June 2002) The Science This THEMIS visible image shows the effects of erosion on a beautiful sequence of dramatically layered rocks within Candor Chasma, which is part of the Valles Marineris. These layers were initially deposited within Candor, and have subsequently been eroded by a variety of processes, including wind and downslope motion due to gravity. The effect of erosion is manifest differently in the different layers and at different locations within the layered material. For example, the upper portion of the Candor deposit seen in the lower one-third of the image appears more intact, whereas downslope there is pronounced fluting to create produced "spur and gully" slopes. Relatively dark materials are seen throughout the image and appear to mantle select areas of the layered deposits. When seen in other areas by THEMIS, and at higher resolution by the Mars Global Surveyor camera, these dark materials often form sand dunes. The dark mantling material in Candor is likely dark sand as well. Several particularly dark patches can be seen near the left (western) edge of the image, approximately one quarter of the way up from the bottom of the image. Very few impact craters of any size can be seen in this image, indicating that the erosion and transport of material is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded. The Story The smooth, triangular shape near the center of this image is the plateau of a canyon, with walls that dramatically descend on either side. This canyon is named Chasma, which means "blaze" or "white" in Latin. The lighter, brighter material of the southern canyon wall displays erosional streaks that almost do happen to look like a white blaze. Toward the bottom left of the image, you can see how the relatively brighter material from the top has been carried down to the bottom. Notice that the upper, grayer part of the southern canyon walls don't seem to have the same erosional flutes as the brighter material just below it. By looking at such differences on the same canyon wall, geologists can begin to understand the kinds of materials that make up each layer of the canyon wall, and how resistant each is to erosion. No matter what part of the canyon you look at, erosion has created the beautiful sequence of layered rocks within Candor. Sometimes it's the wind that acts, and sometimes gravity, which pulls material from the upper parts of the canyon downslope. Be sure to click on the above image for a close-up view of all of the subtle layers and ripples. Look also for some dark, almost black patches (bottom left, about a quarter of the way up). These dark splotches are most likely made of sand. In fact, much of the darker areas seen in this image are probably made of sand. The sand often forms in dunes, as both THEMIS and the higher resolution camera on Mars Global Surveyor, Odyssey's sister orbiter, have shown. With all of the wind and downslope erosion,, , this area is fairly active geologically. You can tell because there are very few impact craters of any size to be seen. That means material is being transported at a rate that's rapid enough to bury or erode any craters that do form. Candor Chasma is part of Valles Marineris, the large canyon system that slices across a large part of the red planet. If Valles Marineris were located on Earth, it would stretch all the way from the west coast to the east coast of the United States.
Candor Chasma
PIA03838
Sol (our sun)
Thermal Emission Imaging Sys …
Title Candor Chasma
Original Caption Released with Image (Released 27 June 2002) The Science This THEMIS visible image shows the effects of erosion on a beautiful sequence of dramatically layered rocks within Candor Chasma, which is part of the Valles Marineris. These layers were initially deposited within Candor, and have subsequently been eroded by a variety of processes, including wind and downslope motion due to gravity. The effect of erosion is manifest differently in the different layers and at different locations within the layered material. For example, the upper portion of the Candor deposit seen in the lower one-third of the image appears more intact, whereas downslope there is pronounced fluting to create produced "spur and gully" slopes. Relatively dark materials are seen throughout the image and appear to mantle select areas of the layered deposits. When seen in other areas by THEMIS, and at higher resolution by the Mars Global Surveyor camera, these dark materials often form sand dunes. The dark mantling material in Candor is likely dark sand as well. Several particularly dark patches can be seen near the left (western) edge of the image, approximately one quarter of the way up from the bottom of the image. Very few impact craters of any size can be seen in this image, indicating that the erosion and transport of material is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded. The Story The smooth, triangular shape near the center of this image is the plateau of a canyon, with walls that dramatically descend on either side. This canyon is named Chasma, which means "blaze" or "white" in Latin. The lighter, brighter material of the southern canyon wall displays erosional streaks that almost do happen to look like a white blaze. Toward the bottom left of the image, you can see how the relatively brighter material from the top has been carried down to the bottom. Notice that the upper, grayer part of the southern canyon walls don't seem to have the same erosional flutes as the brighter material just below it. By looking at such differences on the same canyon wall, geologists can begin to understand the kinds of materials that make up each layer of the canyon wall, and how resistant each is to erosion. No matter what part of the canyon you look at, erosion has created the beautiful sequence of layered rocks within Candor. Sometimes it's the wind that acts, and sometimes gravity, which pulls material from the upper parts of the canyon downslope. Be sure to click on the above image for a close-up view of all of the subtle layers and ripples. Look also for some dark, almost black patches (bottom left, about a quarter of the way up). These dark splotches are most likely made of sand. In fact, much of the darker areas seen in this image are probably made of sand. The sand often forms in dunes, as both THEMIS and the higher resolution camera on Mars Global Surveyor, Odyssey's sister orbiter, have shown. With all of the wind and downslope erosion,, , this area is fairly active geologically. You can tell because there are very few impact craters of any size to be seen. That means material is being transported at a rate that's rapid enough to bury or erode any craters that do form. Candor Chasma is part of Valles Marineris, the large canyon system that slices across a large part of the red planet. If Valles Marineris were located on Earth, it would stretch all the way from the west coast to the east coast of the United States.
1-15 of 15