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Advanced Communication Technology Satellite (ACTS) and Earth
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Weddell Sea, Antarctica L, C
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This Spaceborne Imaging Rada
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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. |
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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. |
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Planet Temperatures
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Planet Temperatures |
| description |
In general, the surface temperature of the planets decreases with increasing distance from the Sun. Venus is an exception because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead (3280C). Mercury rotates slowly and has a thin atmosphere, and consequently, the nightside temperature can be more than 5000C lower than the dayside temperature shown on the diagram. Temperatures for the gas giants (Jupiter, Saturn, Uranus, and Neptune) are shown at a level in the atmosphere equal in pressure to sea level on Earth. Temperatures are in both Fahrenheit and Celsius, and the planets are not shown to scale. *Image Credit*: Lunar and Planetary Institute |
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Hubble Discovers Powerful La
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| Title |
Hubble Discovers Powerful Laser Beamed from Chaotic Star |
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STS-51 Launch
| Photo Description |
The Space Shuttle Discovery takes off from Launch Pad 39B at the Kennedy Space Center, Florida, to begin Mission STS-51 on 12 September 1993. The 57th shuttle mission began at 7:45 a.m. EDT, and lasted 9 days, 20 hours, 11 minutes, 11 seconds, while traveling a total distance of 4,106,411 miles. The Advanced Communications Technology Satellite (ACTS) was one of the projects deployed. This satellite serves as a test bed for advanced experimental communications satellite concepts and technology. Another payload on this mission was the Orbiting Retrievable Far and Extreme Ultraviolet Spectrometer (ORFEUS) telescope mounted on the Shuttle Pallet Satellite (SPAS) payload carrier. ORFEUS was designed to investigate very hot and very cold matter in the universe. |
| Project Description |
470,000 pounds. The engines burn a mixture of liquid oxygen and liquid hydrogen. In orbit, the Space Shuttles circle the earth at a speed of 17,500 miles per hour with each orbit taking about 90 minutes. A Space Shuttle crew sees a sunrise or sunset every 45 minutes. When Space Shuttle flights began in April 1981, Dryden Flight Research Center, Edwards, California, was the primary landing site for the Shuttles. Now Kennedy Space Center, Florida, is the primary landing site with Dryden remaining as the principal alternate landing site., Space Shuttles are the main element of America?s Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy, weather forecasting, navigation, oceanographic studies, and other scientific fields. The Space Shuttles can also launch spacecraft into orbits higher than the Shuttle?s altitude limit through the use of Inertial Upper Stage (IUS) propulsion units. After release from the Space Shuttle payload bay, the IUS is ignited to carry the spacecraft into deep space. The Space Shuttles are also being used to carry elements of the International Space Station into space where they are assembled in orbit. The Space Shuttles were built by Rockwell International?s Space Transportation Systems Division, Downey, California. Rockwell?s Rocketdyne Division (now part of Boeing) builds the three main engines, and Thiokol, Brigham City, Utah, makes the solid rocket booster motors. Martin Marietta Corporation (now Lockheed Martin), New Orleans, Louisiana, makes the external tanks. Each orbiter (Space Shuttle) is 121 feet long, has a wingspan of 78 feet, and a height of 57 feet. The Space Shuttle is approximately the size of a DC-9 commercial airliner and can carry a payload of 65,000 pounds into orbit. The payload bay is 60 feet long and 15 feet in diameter. Each main engine is capable of producing a sea level thrust of 375,000 pounds and a vacuum (orbital) thrust of |
| Photo Date |
October 1993 |
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STS-54 Onboard Photograph-Ex
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| Name of Image |
STS-54 Onboard Photograph-External Tank Separation |
| Date of Image |
1993-01-01 |
| Full Description |
This STS-54 mission onboard photograph shows the external tank (ET) falling toward the Earth following its jettisoning from the Shuttle orbiter Endeavour. The giant cylinder, higher than a 15-story building, with a length of 154-feet (47-meters) and a diameter of 27.5-feet (8.4-meters), is the largest single piece of the Space Shuttle. During launch, the ET also acts as a backbone for the orbiter and solid rocket boosters. In separate, internal pressurized tank sections, the ET holds the liquid hydrogen fuel and liquid oxygen oxidizer for the Shuttle's three main engines. During launch, the ET feeds the fuel under pressure through 17-inch (43.2- centimeter) ducts that branch off into smaller lines that feed directly into the main engines. Some 64,000 gallons (242,260 liters) of fuel are consumed by the main engines each minute. Machined from aluminum alloys, the Space Shuttle's external tank is the only part of the launch vehicle that currently is not reused. After its 526,000 gallons (1,991,071 liters) of propellants are consumed during the first 8.5 minutes of flight, it is jettisoned from the orbiter and breaks up in the upper atmosphere, its pieces falling into remote ocean waters. The Marshall Space Flight Center was responsible for developing the ET. |
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2005 Ozone Hole
| Title |
2005 Ozone Hole |
| Description |
The year 2005 marks the twentieth anniversary of the discovery of the ozone hole and the first full year that NASA's Aura satellite has provided detailed images of the hole. Aura was launched in 2004 to monitor the Earth's atmosphere, including the health of the delicate ozone layer. The Ozone Monitoring Instrument on Aura collected the data used to create this image on September 11, 2005, when the ozone hole covered 27 million square kilometers—its peak size for the season. Deep blue shows where ozone levels were low enough to be considered part of the ozone hole. New research shows that the ozone layer may be slower in recovering than previously thought. Ozone is a highly reactive colorless gas that contains three oxygen atoms. Near the surface of the Earth, ozone is hazardous to human health, causing problems like lung irritation, but high in the atmosphere, ozone acts as a crucial shield that absorbs harmful ultraviolet radiation from the Sun. The ozone hole is not an actual hole, but a place in the atmosphere where the protective layer of ozone has worn thin. In 1985, Joseph Farman, Brian Gardiner, and Jonathan Shanklin discovered in the ozone hole over Antarctica. In the following two years, scientists confirmed that human-produced chemicals, chlorofluorocarbons, used in refrigeration and propellant devices, were causing the hole. Chlorofluorocarbons contain high levels of chlorine, which breaks free from the larger molecules in the bitter cold and darkness of Antarctic and Arctic winter. Through a series of chemical reactions, the free chlorine becomes a two-atom molecule of chlorine gas. When sunlight returns, the chlorine gas disintegrates into separate chlorine atoms, which catalyze the destruction of atmospheric ozone. Though the production of chlorofluorocarbons was restricted in 1987, reservoirs of the chemicals in existing refrigerators and air conditioners are still emitting ozone-depleting chemicals into the atmosphere at higher levels than predicted, new measurements show. The extra chemicals may delay the recovery of the ozone hole until about 2065. Previous models predicted a recovery of the ozone layer by 2050. These results were announced on December 6, 2005, at the fall meeting of the American Geophysical Union. To read more, see Ozone Hole: Prospects for Recovery [ http://www.nasa.gov/centers/goddard/news/topstory/2005/ozone_recovery.html ] on the NASA Goddard News web page. To read more about the ozone hole and NASA's mission to study it, check out Ozone Hole Watch [ http://ozonewatch.gsfc.nasa.gov/facts/hole.html ]. The site also contains daily images of the ozone hole as measured by Aura's Ozone Monitoring Instrument. NASA image and animations courtesy GSFC Ozone Processing Team, [ http://toms.gsfc.nasa.gov/ ] based on data provided by the Ozone Monitoring Instrument [ http://www.knmi.nl/omi/publ-en/news/index.html ] (OMI) |
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2005 Ozone Hole
| Title |
2005 Ozone Hole |
| Description |
The year 2005 marks the twentieth anniversary of the discovery of the ozone hole and the first full year that NASA's Aura satellite has provided detailed images of the hole. Aura was launched in 2004 to monitor the Earth's atmosphere, including the health of the delicate ozone layer. The Ozone Monitoring Instrument on Aura collected the data used to create this image on September 11, 2005, when the ozone hole covered 27 million square kilometers—its peak size for the season. Deep blue shows where ozone levels were low enough to be considered part of the ozone hole. New research shows that the ozone layer may be slower in recovering than previously thought. Ozone is a highly reactive colorless gas that contains three oxygen atoms. Near the surface of the Earth, ozone is hazardous to human health, causing problems like lung irritation, but high in the atmosphere, ozone acts as a crucial shield that absorbs harmful ultraviolet radiation from the Sun. The ozone hole is not an actual hole, but a place in the atmosphere where the protective layer of ozone has worn thin. In 1985, Joseph Farman, Brian Gardiner, and Jonathan Shanklin discovered in the ozone hole over Antarctica. In the following two years, scientists confirmed that human-produced chemicals, chlorofluorocarbons, used in refrigeration and propellant devices, were causing the hole. Chlorofluorocarbons contain high levels of chlorine, which breaks free from the larger molecules in the bitter cold and darkness of Antarctic and Arctic winter. Through a series of chemical reactions, the free chlorine becomes a two-atom molecule of chlorine gas. When sunlight returns, the chlorine gas disintegrates into separate chlorine atoms, which catalyze the destruction of atmospheric ozone. Though the production of chlorofluorocarbons was restricted in 1987, reservoirs of the chemicals in existing refrigerators and air conditioners are still emitting ozone-depleting chemicals into the atmosphere at higher levels than predicted, new measurements show. The extra chemicals may delay the recovery of the ozone hole until about 2065. Previous models predicted a recovery of the ozone layer by 2050. These results were announced on December 6, 2005, at the fall meeting of the American Geophysical Union. To read more, see Ozone Hole: Prospects for Recovery [ http://www.nasa.gov/centers/goddard/news/topstory/2005/ozone_recovery.html ] on the NASA Goddard News web page. To read more about the ozone hole and NASA's mission to study it, check out Ozone Hole Watch [ http://ozonewatch.gsfc.nasa.gov/facts/hole.html ]. The site also contains daily images of the ozone hole as measured by Aura's Ozone Monitoring Instrument. NASA image and animations courtesy GSFC Ozone Processing Team, [ http://toms.gsfc.nasa.gov/ ] based on data provided by the Ozone Monitoring Instrument [ http://www.knmi.nl/omi/publ-en/news/index.html ] (OMI) |
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2005 Ozone Hole
| Title |
2005 Ozone Hole |
| Description |
The year 2005 marks the twentieth anniversary of the discovery of the ozone hole and the first full year that NASA's Aura satellite has provided detailed images of the hole. Aura was launched in 2004 to monitor the Earth's atmosphere, including the health of the delicate ozone layer. The Ozone Monitoring Instrument on Aura collected the data used to create this image on September 11, 2005, when the ozone hole covered 27 million square kilometers—its peak size for the season. Deep blue shows where ozone levels were low enough to be considered part of the ozone hole. New research shows that the ozone layer may be slower in recovering than previously thought. Ozone is a highly reactive colorless gas that contains three oxygen atoms. Near the surface of the Earth, ozone is hazardous to human health, causing problems like lung irritation, but high in the atmosphere, ozone acts as a crucial shield that absorbs harmful ultraviolet radiation from the Sun. The ozone hole is not an actual hole, but a place in the atmosphere where the protective layer of ozone has worn thin. In 1985, Joseph Farman, Brian Gardiner, and Jonathan Shanklin discovered in the ozone hole over Antarctica. In the following two years, scientists confirmed that human-produced chemicals, chlorofluorocarbons, used in refrigeration and propellant devices, were causing the hole. Chlorofluorocarbons contain high levels of chlorine, which breaks free from the larger molecules in the bitter cold and darkness of Antarctic and Arctic winter. Through a series of chemical reactions, the free chlorine becomes a two-atom molecule of chlorine gas. When sunlight returns, the chlorine gas disintegrates into separate chlorine atoms, which catalyze the destruction of atmospheric ozone. Though the production of chlorofluorocarbons was restricted in 1987, reservoirs of the chemicals in existing refrigerators and air conditioners are still emitting ozone-depleting chemicals into the atmosphere at higher levels than predicted, new measurements show. The extra chemicals may delay the recovery of the ozone hole until about 2065. Previous models predicted a recovery of the ozone layer by 2050. These results were announced on December 6, 2005, at the fall meeting of the American Geophysical Union. To read more, see Ozone Hole: Prospects for Recovery [ http://www.nasa.gov/centers/goddard/news/topstory/2005/ozone_recovery.html ] on the NASA Goddard News web page. To read more about the ozone hole and NASA's mission to study it, check out Ozone Hole Watch [ http://ozonewatch.gsfc.nasa.gov/facts/hole.html ]. The site also contains daily images of the ozone hole as measured by Aura's Ozone Monitoring Instrument. NASA image and animations courtesy GSFC Ozone Processing Team, [ http://toms.gsfc.nasa.gov/ ] based on data provided by the Ozone Monitoring Instrument [ http://www.knmi.nl/omi/publ-en/news/index.html ] (OMI) |
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Breakup of the World's Large
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| 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). |
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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). |
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Earthquake Spawns Tsunamis
| Title |
Earthquake Spawns Tsunamis |
| Description |
The Earth?s solid surface floats on a layer of softer rock as a collection of interlocking, movable puzzle pieces called tectonic plates. At 7:58 a.m. (local time), on December 26, 2004, beneath the Indian Ocean west of Sumatra, Indonesia, pent-up energy from the compressional forces of one tectonic plate grinding under another found a weak spot in the overlying rock. The rock was thrust upward, and the Earth shook as a 9.0 magnitude earthquake sent its vibrations out into the ocean. Tsunamis spread out in all directions, the massive waves washed over islands and crashed against coastlines in Sri Lanka, Southern India, and even the east coast of Africa. Tens of thousands of people were killed, millions are homeless. The image above shows how the tectonic puzzle pieces fit together around Indonesia. The epicenter of the recent quake is marked with a red star in the image. It is located just to the east of the Sunda Trench, where the India Plate begins to get subducted beneath (forced under) the Burma Plate. The blue arrows along the plate boundary show the direction of subduction. As the India Plate slides beneath the Burma Plate, it meets pockets of resistance, which causes compressional forces to build up. Weakened overlying rock gets forced upward. Based on the location of aftershocks (red shaded circles on the image), the United States Geological Survey reports that approximately 1,200 kilometers of the plate boundary probably slipped as a result of the quake. The initial rupture was likely more than 100 kilometers wide, and probably produced an average vertical displacement along the fault plane (the slope along which the two plates meet) of 15 meters. When the bottom of the ocean is deformed by this type of ?megathrust? quake, the upward force acts like a fist rising up from underwater. Water rolls down off the sides of the ?fist,? creating massive waves that can travel as fast as an airplane. The waves can move across the ocean and barely disturb the surface, but when they reach shallow coastal water, the earthquake?s energy thrusts them tens of meters into the air. The tsunami created by this earthquake reached India and Sri Lanka in about four hours. The wave eventually reached Africa, the Pacific Ocean, Hawaii, and the west coast of North and South America. For more information about this earthquake and plate tectonics, visit the Website of the USGS. [ http://earthquake.usgs.gov/eqinthenews/2004/usslav/ ] Image courtesy United States Geological Survey [ http://www.usgs.gov/ ] |
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Lake Valencia, Venezuela
| Title |
Lake Valencia, Venezuela |
| Description |
Lago de Valencia (Lake Valencia) is located in north-central Venezuela and is the largest freshwater lake in the country. The lake was formed approximately 2-3 million years ago due to faulting and subsequent damming of the Valencia River. The lake has been completely dry during several discrete periods of its geologic history. Since 1976 Lake Valencia water levels have risen due to diversion of water from neighboring watersheds—it currently acts as a reservoir for the surrounding urban centers (such as Maracay). The vivid green algal blooms present in this image result from a continual influx of untreated wastewater from the surrounding urban, agricultural, and industrial land uses. This contributes to ongoing eutrophication, contamination, and salinization of the lake. Despite its picturesque location between the Cordillera de la Costa to the north and the Serrania del Interior to the south, Lake Valencia's poor water quality limits opportunities for tourism and recreational activities. Astronaut photograph ISS010-E-5194 [ http://eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=5194 ] was acquired October 27, 2004 with a Kodak K-760C digital camera with a 180 mm lens and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The International Space Station Program [ http://spaceflight.nasa.gov/ ] supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. [ http://eol.jsc.nasa.gov/ ] |
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3C175: Quasar Cannon
| Title |
3C175: Quasar Cannon |
| Explanation |
3C175 is not only a quasar, it is a galaxy-fueled particle cannon. Visible as the central dot is quasar [ http://oposite.stsci.edu/pubinfo/PR/96/35/quasar.html ] 3C175, the active center of a galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap961125.html ] so distant [ http://isaac.exploratorium.edu/~pauld/activities/astronomy/cityuniversesize.html ] that the light we see from it was emitted when the Earth [ http://antwrp.gsfc.nasa.gov/apod/ap001127.html ] was just forming [ http://www.astro.psu.edu/users/niel/scales/geohist1.ascii ]. The above image [ http://www.cv.nrao.edu/~abridle/3c175.htm ] was recorded in radio waves [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html ] by an array of house-sized telescopes called the Very Large Array [ http://antwrp.gsfc.nasa.gov/apod/ap000530.html ] (VLA). Shooting out from 3C175 is a thin jet [ http://antwrp.gsfc.nasa.gov/apod/ap000706.html ] of protons [ http://hyperphysics.phy-astr.gsu.edu/hbase/particles/proton.html ] and electrons [ http://www.aip.org/history/electron/ ] traveling near the speed of light [ http://www.what-is-the-speed-of-light.com/ ] that is over one million light-years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] long. The jet [ http://antwrp.gsfc.nasa.gov/apod/ap000619.html ] acts like a particle cannon [ http://www.pbs.org/tesla/ll/ll_wendwar.html ] and bores through gas cloud in its path. How this jet [ http://antwrp.gsfc.nasa.gov/apod/ap010816.html ] forms and why it is so narrow remain topics of current [ http://adsabs.harvard.edu/cgi-bin/bib_query?1994AJ....108..766B ] research [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999ApJ...511...84H ]. |
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STS-51 Launch
| Title |
STS-51 Launch |
| Description |
Shuttles were built by Rockwell International's Space Transportation Systems Division, Downey, California. Rockwell's Rocketdyne Division (now part of Boeing) builds the three main engines, and Thiokol, Brigham City, Utah, makes the solid rocket booster motors. Martin Marietta Corporation (now Lockheed Martin), New Orleans, Louisiana, makes the external tanks. Each orbiter (Space Shuttle) is 121 feet long, has a wingspan of 78 feet, and a height of 57 feet. The Space Shuttle is approximately the size of a DC-9 commercial airliner and can carry a payload of 65,000 pounds into orbit. The payload bay is 60 feet long and 15 feet in diameter. Each main engine is capable of producing a sea level thrust of 375,000 pounds and a vacuum (orbital) thrust of 470,000 pounds. The engines burn a mixture of liquid oxygen and liquid hydrogen. In orbit, the Space Shuttles circle the earth at a speed of 17,500 miles per hour with each orbit taking about 90 minutes. A Space Shuttle crew sees a sunrise or sunset every 45 minutes. When Space Shuttle flights began in April 1981, Dryden Flight Research Center, Edwards, California, was the primary landing site for the Shuttles. Now Kennedy Space Center, Florida, is the primary landing site with Dryden remaining as the principal alternate landing site., The Space Shuttle Discovery takes off from Launch Pad 39B at the Kennedy Space Center, Florida, to begin Mission STS-51 on 12 September 1993. The 57th shuttle mission began at 7:45 a.m. EDT, and lasted 9 days, 20 hours, 11 minutes, 11 seconds, while traveling a total distance of 4,106,411 miles. The Advanced Communications Technology Satellite (ACTS) was one of the projects deployed. This satellite serves as a test bed for advanced experimental communications satellite concepts and technology. Another payload on this mission was the Orbiting Retrievable Far and Extreme Ultraviolet Spectrometer (ORFEUS) telescope mounted on the Shuttle Pallet Satellite (SPAS) payload carrier. ORFEUS was designed to investigate very hot and very cold matter in the universe. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy, weather forecasting, navigation, oceanographic studies, and other scientific fields. The Space Shuttles can also launch spacecraft into orbits higher than the Shuttle's altitude limit through the use of Inertial Upper Stage (IUS) propulsion units. After release from the Space Shuttle payload bay, the IUS is ignited to carry the spacecraft into deep space. The Space Shuttles are also being used to carry elements of the International Space Station into space where they are assembled in orbit. The Space |
| Date |
10.01.1993 |
|
Permafrost on Mars and Earth
…
nasa, nasaimageofthedaygalle
…
* http://www.nasa.gov/missio
…
permafrost_earth_mars
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-05-25 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
permafrost_earth_mars |
|
Berkeley Pit: Butte, Montana
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nasa, nasaimageofthedaygalle
…
Mined for gold, silver, and
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ISS013-E-63766
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-08-02 |
| creator |
NASA -- Astronaut photograph eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS013&roll=E&frame=63766 ISS013-E-63766 was acquired August 2, 2006, with a Kodak 760C digital camera using an 800 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. spaceflight.nasa.gov/home/index.html The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC eol.jsc.nasa.gov/ Gateway to Astronaut Photography of Earth. |
| identifier |
ISS013-E-63766 |
|
TRMM 3-Year Anniversary : Im
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nasa, nasaimageofthedaygalle
…
Ever wonder about the rainBe
…
trmm_3year
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2000 |
| creator |
NASA -- Image courtesy TRMM Science team and the NASA GSFC svs.gsfc.nasa.gov/ Scientific Visualization Studio. |
| identifier |
trmm_3year |
|
Breakup of the World's Large
…
nasa, nasaimageofthedaygalle
…
Iceberg B-15A was the larges
…
PIA04344
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2000-10-26 |
| creator |
NASA -- Image courtesy NASA/GSFC/LaRC/JPL, www-misr.jpl.nasa.gov/ MISR Team . Text by Clare Averill (Raytheon/JPL). |
| identifier |
PIA04344 |
|
Mega-iceberg A53a, South Atl
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nasa, nasaimageofthedaygalle
…
The mega-iceberg A53a (upper
…
ISS016-E-23196
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-01-15 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ISS016-E-23196 |
|
Mega-iceberg A53a, South Atl
…
nasa, nasaimageofthedaygalle
…
The mega-iceberg A53a (upper
…
ISS016-E-23196
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-01-15 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ISS016-E-23196 |
|
Clouds and Ice of East Antar
…
nasa, nasaimageofthedaygalle
…
These views from the Multi-a
…
PIA03734
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-10-25 |
| creator |
NASA -- Image courtesy NASA/GSFC/LaRC/JPL, www-misr.jpl.nasa.gov/ MISR Team. Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory), and Helen A. Fricker (Scripps Institution of Oceanography). |
| identifier |
PIA03734 |
|
Antarctic Temperature Trend
…
nasa, nasaimageofthedaygalle
…
(Editor's note: This image w
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antarctic_temps.AVH1982-2004
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-04-27 |
| creator |
NASA -- NASA image based on data provided by Josefino Comiso, NASA-GSFC. |
| identifier |
antarctic_temps.AVH1982-2004 |
|
2005 Ozone Hole: Image of th
…
nasa, nasaimageofthedaygalle
…
* eoimages.gsfc.nasa.gov/ima
…
antarctica_omi_2005254
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-09-11 |
| creator |
NASA -- NASA image and animations courtesy GSFC toms.gsfc.nasa.gov/ Ozone Processing Team, based on data provided by the www.knmi.nl/omi/publ-en/news/index.html Ozone Monitoring Instrument (OMI) |
| identifier |
antarctica_omi_2005254 |
|
2005 Ozone Hole: Image of th
…
nasa, nasaimageofthedaygalle
…
* eoimages.gsfc.nasa.gov/ima
…
antarctica_omi_2005254
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-09-11 |
| creator |
NASA -- NASA image and animations courtesy GSFC toms.gsfc.nasa.gov/ Ozone Processing Team, based on data provided by the www.knmi.nl/omi/publ-en/news/index.html Ozone Monitoring Instrument (OMI) |
| identifier |
antarctica_omi_2005254 |
|
Dallas, Texas: Image of the
…
nasa, nasaimageofthedaygalle
…
The Dallas-Fort Worth metrop
…
ISS010-E-24596
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-04-14 |
| creator |
NASA -- Astronaut photograph eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=24596 ISS010-E-24596 was acquired April 14, 2005, with a Kodak 760C digital camera with a 180 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The spaceflight.nasa.gov/home/index.html International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC eol.jsc.nasa.gov/ Gateway to Astronaut Photography of Earth. |
| identifier |
ISS010-E-24596 |
|
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
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PIA01525
Sol (our sun)
Altimeter
| Title |
TOPEX/El Niño Watch - La Niña Weakening, January 17, 1999 |
| Original Caption Released with Image |
This image of the Pacific Ocean was produced using sea-surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on January 17, 1999, sea surface height is an indicator of the heat content of the ocean. This image shows that the unusual large-scale warming (shown here in red and white) in the northwest Pacific that was first observed by the satellite in November 1998 has increased in size and spread east to the central Pacific and south to the equator. The low sea level or cold pool of water along the equator, commonly referred to as La Niña (shown in purple), has weakened in size and heat content during the last several months. Although weakening, the La Niña pattern continues to exert a strong influence on the worldwide climate system. According to oceanographers, the cold La Niña water acts like a boulder in a stream, steering the planet's prevailing winds and changing the course of storms that are born over the ocean. Equally important to North America's winter weather is the very large area of unusually warm Western Pacific ocean. Although the appearance of this feature is not fully understood or anticipated, it is adding energy to the winter storms coming out of the North Pacific which is fueling the very volatile weather over the continental U.S. In this image, the white areas show the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal, in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions. The purple areas are 14 to 18 centimeters (6 to 7 inches) below normal and the blue areas are 5 to 13 centimeters (2 to 5 inches) below normal. For more information, please visit the TOPEX/Poseidon project web page at http://topex-www.jpl.nasa.gov |
|
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
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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. |
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Candor Chasma
PIA03838
Sol (our sun)
Thermal Emission Imaging Sys
…
| Title |
Candor Chasma |
| Original Caption Released with Image |
(Released 27 June 2002) The Science This THEMIS visible image shows the effects of erosion on a beautiful sequence of dramatically layered rocks within Candor Chasma, which is part of the Valles Marineris. These layers were initially deposited within Candor, and have subsequently been eroded by a variety of processes, including wind and downslope motion due to gravity. The effect of erosion is manifest differently in the different layers and at different locations within the layered material. For example, the upper portion of the Candor deposit seen in the lower one-third of the image appears more intact, whereas downslope there is pronounced fluting to create produced "spur and gully" slopes. Relatively dark materials are seen throughout the image and appear to mantle select areas of the layered deposits. When seen in other areas by THEMIS, and at higher resolution by the Mars Global Surveyor camera, these dark materials often form sand dunes. The dark mantling material in Candor is likely dark sand as well. Several particularly dark patches can be seen near the left (western) edge of the image, approximately one quarter of the way up from the bottom of the image. Very few impact craters of any size can be seen in this image, indicating that the erosion and transport of material is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded. The Story The smooth, triangular shape near the center of this image is the plateau of a canyon, with walls that dramatically descend on either side. This canyon is named Chasma, which means "blaze" or "white" in Latin. The lighter, brighter material of the southern canyon wall displays erosional streaks that almost do happen to look like a white blaze. Toward the bottom left of the image, you can see how the relatively brighter material from the top has been carried down to the bottom. Notice that the upper, grayer part of the southern canyon walls don't seem to have the same erosional flutes as the brighter material just below it. By looking at such differences on the same canyon wall, geologists can begin to understand the kinds of materials that make up each layer of the canyon wall, and how resistant each is to erosion. No matter what part of the canyon you look at, erosion has created the beautiful sequence of layered rocks within Candor. Sometimes it's the wind that acts, and sometimes gravity, which pulls material from the upper parts of the canyon downslope. Be sure to click on the above image for a close-up view of all of the subtle layers and ripples. Look also for some dark, almost black patches (bottom left, about a quarter of the way up). These dark splotches are most likely made of sand. In fact, much of the darker areas seen in this image are probably made of sand. The sand often forms in dunes, as both THEMIS and the higher resolution camera on Mars Global Surveyor, Odyssey's sister orbiter, have shown. With all of the wind and downslope erosion,, , this area is fairly active geologically. You can tell because there are very few impact craters of any size to be seen. That means material is being transported at a rate that's rapid enough to bury or erode any craters that do form. Candor Chasma is part of Valles Marineris, the large canyon system that slices across a large part of the red planet. If Valles Marineris were located on Earth, it would stretch all the way from the west coast to the east coast of the United States. |
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| General Description |
STS-116 Shuttle Mission Imagery |
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ACTS\TOS leaves cargo bay on
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| Title |
ACTS\TOS leaves cargo bay on flight day one |
| Description |
The Advanced Communications Technology Satellite (ACTS) with its Transfer Orbit Stage (TOS) leaves the cargo bay of the Earth orbiting Space Shuttle Discovery on Flight Day one. |
| Date Taken |
1993-09-12 |
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ACTS/TOS after release from
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| Title |
ACTS/TOS after release from Shuttle Discovery |
| Description |
The Advanced Communications Technology Satellite (ACTS) with its Transfer Orbit Stage (TOS) is backdropped over the blue ocean following its release from the Earth-orbiting Space Shuttle Discovery. ACTS/TOS deploy was the first major task performed on the almost ten-day mission. |
| Date Taken |
1993-09-12 |
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STS-55 Earth observation of
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| Title |
STS-55 Earth observation of the Timor Sea |
| Description |
STS-55 Earth observation taken from Columbia, Orbiter Vehicle (OV) 102, shows the Timor Sea along the south coast of Timor. The sunglint pattern shows a sharp boundary in sea surface temperature, with cooler water along the coast and warmer water offshore. The sunglint brightness reveals water surface roughness with bright indicating smooth water and dark representing rough water. Cooler water is smoother because it acts to stabilize the atmospheric boundary layer, while the warm water acts to destabilize the atmosphere. Another indication of water temperature is the cloud pattern. Advection within the atmosphere as a result of warming at the sea surface forms low-level clouds with the small, popcorn-like appearance seen in upper right corner of the photograph. The cool water, on the other hand, is relatively free of the popcorn-like clouds. The distribution of the clouds indicates that the wind is blowing toward the upper right corner of the photograph. Also note the line of low-level |
| Date Taken |
1993-05-06 |
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STS-65 Earth observation of
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| Title |
STS-65 Earth observation of dust plumes from Rio Grande in Southern Bolivia |
| Description |
STS-65 Earth observation taken aboard Columbia, Orbiter Vehicle (OV) 102, is of dust plumes from the Rio Grande in Southern Bolivia. A series of dust plumes can be seen rising from sand banks in the Rio Grande of southern Bolivia, bottom right of this northeast-looking view. The Rio Grande brings sediment from the Andes (foothills visible in the foreground, bottom left) and flows across the flat country of the northern Chaco plain. During the low-flow season, sand banks of this sediment are exposed to northerly winds which often blow dust into the surrounding forest. One of the significances of the dust plumes is that dust acts as a source of nutrient for the local soils. This is the most impressive example of dust ever recorded on Shuttle photography from this river. Such plumes have been seen on photographs from four previous missions (STS-31, STS-47, STS-48, STS-51I) emanating from the Rio Grande. The plumes are regularly space because the sand is blown only from those reaches of th |
| Date Taken |
1994-07-23 |
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