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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Hubble Hunts Down Binary Obj
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| Title |
Hubble Hunts Down Binary Objects at the Fringe of Our Solar System |
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Proteus UAV collision-avoida
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Proteus UAV collision-avoida
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Proteus UAV collision-avoida
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Proteus aircraft low-level f
…
| Photo Description |
Proteus aircraft low-level flyby at Las Cruces Airport. |
| Project Description |
The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. Designed by Burt Rutan, president of Scaled Composites, LLC, of Mojave, Calif., Proteus is an "optionally piloted" aircraft ordinarily flown by two pilots in a pressurized cabin. However, it also has the capability to perform its missions semi-autonomously or flown remotely from the ground. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows Proteus to be reconfigured for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. Proteus has an all-composite airframe with graphite-epoxy sandwich construction. Its wingspan of 77 feet 7 inches is expandable to 92 feet with removable wingtips installed. Proteus is 56.3 feet long, 17.6 feet high and weighs 5,900 pounds empty. Proteus is powered by two Williams FJ44-2 turbofan engines, each rated at 2,300 pounds of thrust. Flight testing of the Proteus began in the summer of 1998 at Mojave Airport and continued through the end of 1999. Under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, NASA's Dryden Flight Research Center assisted Scaled Composites in developing a sophisticated station-keeping autopilot system and a satellite communications (SATCOM)-based uplink-downlink data system for Proteus' performance and payload data. Flight testing included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, was installed and checked out in several flight tests. The systems performed flawlessly during Proteus' deployment to the Paris Airshow in 1999. NASA has used Proteus as a testbed for a variety of technologies related to maturing unmanned air vehicles (UAVs) for use in civil applications. A small Airborne Real-Time Imaging System (ARTIS) camera, developed by HyperSpectral Sciences, Inc., under NASA's ERAST project, was demonstrated during the summer of 1999 when it took visual and near-infrared photos from Proteus while it was flying high over the Experimental Aircraft Association's "AirVenture 99" Airshow at Oshkosh, Wisc. The images were displayed on a computer monitor at the show only moments after they were taken. In March 2002, NASA Dryden, in cooperation with New Mexico State University's Technical Analysis and Applications Center (TAAC), the FAA and several other entities, conducted flight demonstrations of an active detect, see, and avoid (DSA) system for potential application to unmanned aerial vehicles (UAVs) out of Las Cruces, New Mexico. Proteus was flown as a surrogate UAV controlled remotely from the ground, although safety pilots were aboard to handle takeoff and landing and any potential emergencies. Three other aircraft, ranging from general aviation aircraft to a NASA F/A-18, served as "cooperative" target aircraft with an operating transponder. In each of 18 different scenarios, a Goodrich Skywatch HP Traffic Advisory System (TAS) on the Proteus detected approaching air traffic on potential collision courses, including several scenarios with two aircraft approaching from different directions. The remote pilot then directed Proteus to turn, climb or descend as needed to avoid the potential threat. In April 2003, a second series of flight demonstrations focusing on "non-cooperative" aircraft (those without operating transponders), was conducted in restricted airspace near Mojave, Calif., again using the Proteus as a surrogate UAV. Proteus was equipped with a small Amphitech OASys 35 Ghz primary radar system to detect potential intruder aircraft on simulated collision courses. The radar data was telemetered directly to the ground station as well as via an Inmarsat satellite system installed on Proteus. A mix of seven intruder aircraft, ranging from a sailplane to a high-speed jet, flew 20 scenarios over a four-day period, one or two aircraft at a time. In each case, the radar picked up the intruding aircraft at ranges from 2.5 to 6.5 miles, depending on the intruder's radar signature. Proteus' remote pilot on the ground was able to direct Proteus to take evasive action if needed. Based on the preliminary results of both series of tests, project engineers believe that some upgrades would have to be made to both the Skywatch and the OASys detection systems to maximize their effectiveness as collision-avoidance detection sensors for UAVs. Additional flight tests of other types of detection systems, such as electro-optical infrared devices, may occur in the future under a follow-on program in an effort to establish an equivalent level of safety for UAVs to that now required of manned aircraft. The ERAST Project is sponsored by the Office of Aerospace Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center, Edwards, Calif. |
| Photo Date |
March 15, 2002 |
|
Proteus DSA control room in
…
| Photo Description |
Proteus DSA control room in Mojave, CA (L to R) Jean-Pierre Soucy, Amphitech International Software engineer Craig Bomben, NASA Dryden Test Pilot Pete Siebold, (with headset, at computer controls) Scaled Composites pilot Bob Roehm, New Mexico State University (NMSU) UAV Technical Analysis Application Center (TAAC) Chuck Coleman, Scaled Composites Pilot Kari Sortland, NMSU TAAC Russell Wolfe, Modern Technology Solutions, Inc. Scaled Composites' unique tandem-wing Proteus was the testbed for a series of UAV collision-avoidance flight demonstrations. An Amphitech 35GHz radar unit installed below Proteus' nose was the primary sensor for the Detect, See and Avoid tests. |
| Project Description |
The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. Designed by Burt Rutan, president of Scaled Composites, LLC, of Mojave, Calif., Proteus is an "optionally piloted" aircraft ordinarily flown by two pilots in a pressurized cabin. However, it also has the capability to perform its missions semi-autonomously or flown remotely from the ground. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows Proteus to be reconfigured for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. Proteus has an all-composite airframe with graphite-epoxy sandwich construction. Its wingspan of 77 feet 7 inches is expandable to 92 feet with removable wingtips installed. Proteus is 56.3 feet long, 17.6 feet high and weighs 5,900 pounds empty. Proteus is powered by two Williams FJ44-2 turbofan engines, each rated at 2,300 pounds of thrust. Flight testing of the Proteus began in the summer of 1998 at Mojave Airport and continued through the end of 1999. Under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, NASA's Dryden Flight Research Center assisted Scaled Composites in developing a sophisticated station-keeping autopilot system and a satellite communications (SATCOM)-based uplink-downlink data system for Proteus' performance and payload data. Flight testing included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, was installed and checked out in several flight tests. The systems performed flawlessly during Proteus' deployment to the Paris Airshow in 1999. NASA has used Proteus as a testbed for a variety of technologies related to maturing unmanned air vehicles (UAVs) for use in civil applications. A small Airborne Real-Time Imaging System (ARTIS) camera, developed by HyperSpectral Sciences, Inc., under NASA's ERAST project, was demonstrated during the summer of 1999 when it took visual and near-infrared photos from Proteus while it was flying high over the Experimental Aircraft Association's "AirVenture 99" Airshow at Oshkosh, Wisc. The images were displayed on a computer monitor at the show only moments after they were taken. In March 2002, NASA Dryden, in cooperation with New Mexico State University's Technical Analysis and Applications Center (TAAC), the FAA and several other entities, conducted flight demonstrations of an active detect, see, and avoid (DSA) system for potential application to unmanned aerial vehicles (UAVs) out of Las Cruces, New Mexico. Proteus was flown as a surrogate UAV controlled remotely from the ground, although safety pilots were aboard to handle takeoff and landing and any potential emergencies. Three other aircraft, ranging from general aviation aircraft to a NASA F/A-18, served as "cooperative" target aircraft with an operating transponder. In each of 18 different scenarios, a Goodrich Skywatch HP Traffic Advisory System (TAS) on the Proteus detected approaching air traffic on potential collision courses, including several scenarios with two aircraft approaching from different directions. The remote pilot then directed Proteus to turn, climb or descend as needed to avoid the potential threat. In April 2003, a second series of flight demonstrations focusing on "non-cooperative" aircraft (those without operating transponders), was conducted in restricted airspace near Mojave, Calif., again using the Proteus as a surrogate UAV. Proteus was equipped with a small Amphitech OASys 35 Ghz primary radar system to detect potential intruder aircraft on simulated collision courses. The radar data was telemetered directly to the ground station as well as via an Inmarsat satellite system installed on Proteus. A mix of seven intruder aircraft, ranging from a sailplane to a high-speed jet, flew 20 scenarios over a four-day period, one or two aircraft at a time. In each case, the radar picked up the intruding aircraft at ranges from 2.5 to 6.5 miles, depending on the intruder's radar signature. Proteus' remote pilot on the ground was able to direct Proteus to take evasive action if needed. Based on the preliminary results of both series of tests, project engineers believe that some upgrades would have to be made to both the Skywatch and the OASys detection systems to maximize their effectiveness as collision-avoidance detection sensors for UAVs. Additional flight tests of other types of detection systems, such as electro-optical infrared devices, may occur in the future under a follow-on program in an effort to establish an equivalent level of safety for UAVs to that now required of manned aircraft. The ERAST Project is sponsored by the Office of Aerospace Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center, Edwards, Calif. |
| Photo Date |
April 3, 2003 |
|
Amphitech Radar on Proteus
| Photo Description |
An Amphitech OASys Ka-band radar was the primary sensor installed on Scaled Composites' Proteus for the second phase of NASA-sponsored unmanned aerial vehicle Detect, See and Avoid flight tests. |
| Project Description |
The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. Designed by Burt Rutan, president of Scaled Composites, LLC, of Mojave, Calif., Proteus is an "optionally piloted" aircraft ordinarily flown by two pilots in a pressurized cabin. However, it also has the capability to perform its missions semi-autonomously or flown remotely from the ground. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows Proteus to be reconfigured for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. Proteus has an all-composite airframe with graphite-epoxy sandwich construction. Its wingspan of 77 feet 7 inches is expandable to 92 feet with removable wingtips installed. Proteus is 56.3 feet long, 17.6 feet high and weighs 5,900 pounds empty. Proteus is powered by two Williams FJ44-2 turbofan engines, each rated at 2,300 pounds of thrust. Flight testing of the Proteus began in the summer of 1998 at Mojave Airport and continued through the end of 1999. Under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, NASA's Dryden Flight Research Center assisted Scaled Composites in developing a sophisticated station-keeping autopilot system and a satellite communications (SATCOM)-based uplink-downlink data system for Proteus' performance and payload data. Flight testing included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, was installed and checked out in several flight tests. The systems performed flawlessly during Proteus' deployment to the Paris Airshow in 1999. NASA has used Proteus as a testbed for a variety of technologies related to maturing unmanned air vehicles (UAVs) for use in civil applications. A small Airborne Real-Time Imaging System (ARTIS) camera, developed by HyperSpectral Sciences, Inc., under NASA's ERAST project, was demonstrated during the summer of 1999 when it took visual and near-infrared photos from Proteus while it was flying high over the Experimental Aircraft Association's "AirVenture 99" Airshow at Oshkosh, Wisc. The images were displayed on a computer monitor at the show only moments after they were taken. In March 2002, NASA Dryden, in cooperation with New Mexico State University's Technical Analysis and Applications Center (TAAC), the FAA and several other entities, conducted flight demonstrations of an active detect, see, and avoid (DSA) system for potential application to unmanned aerial vehicles (UAVs) out of Las Cruces, New Mexico. Proteus was flown as a surrogate UAV controlled remotely from the ground, although safety pilots were aboard to handle takeoff and landing and any potential emergencies. Three other aircraft, ranging from general aviation aircraft to a NASA F/A-18, served as "cooperative" target aircraft with an operating transponder. In each of 18 different scenarios, a Goodrich Skywatch HP Traffic Advisory System (TAS) on the Proteus detected approaching air traffic on potential collision courses, including several scenarios with two aircraft approaching from different directions. The remote pilot then directed Proteus to turn, climb or descend as needed to avoid the potential threat. In April 2003, a second series of flight demonstrations focusing on "non-cooperative" aircraft (those without operating transponders), was conducted in restricted airspace near Mojave, Calif., again using the Proteus as a surrogate UAV. Proteus was equipped with a small Amphitech OASys 35 Ghz primary radar system to detect potential intruder aircraft on simulated collision courses. The radar data was telemetered directly to the ground station as well as via an Inmarsat satellite system installed on Proteus. A mix of seven intruder aircraft, ranging from a sailplane to a high-speed jet, flew 20 scenarios over a four-day period, one or two aircraft at a time. In each case, the radar picked up the intruding aircraft at ranges from 2.5 to 6.5 miles, depending on the intruder's radar signature. Proteus' remote pilot on the ground was able to direct Proteus to take evasive action if needed. Based on the preliminary results of both series of tests, project engineers believe that some upgrades would have to be made to both the Skywatch and the OASys detection systems to maximize their effectiveness as collision-avoidance detection sensors for UAVs. Additional flight tests of other types of detection systems, such as electro-optical infrared devices, may occur in the future under a follow-on program in an effort to establish an equivalent level of safety for UAVs to that now required of manned aircraft. The ERAST Project is sponsored by the Office of Aerospace Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center, Edwards, Calif. |
| Photo Date |
April 1, 2003 |
|
Proteus front view in flight
| Photo Description |
Scaled Composites' unique tandem-wing Proteus was the testbed for a series of UAV collision-avoidance flight demonstrations. An Amphitech 35GHz radar unit installed below Proteus' nose was the primary sensor for the Detect, See and Avoid tests. |
| Project Description |
The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. Designed by Burt Rutan, president of Scaled Composites, LLC, of Mojave, Calif., Proteus is an "optionally piloted" aircraft ordinarily flown by two pilots in a pressurized cabin. However, it also has the capability to perform its missions semi-autonomously or flown remotely from the ground. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows Proteus to be reconfigured for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. Proteus has an all-composite airframe with graphite-epoxy sandwich construction. Its wingspan of 77 feet 7 inches is expandable to 92 feet with removable wingtips installed. Proteus is 56.3 feet long, 17.6 feet high and weighs 5,900 pounds empty. Proteus is powered by two Williams FJ44-2 turbofan engines, each rated at 2,300 pounds of thrust. Flight testing of the Proteus began in the summer of 1998 at Mojave Airport and continued through the end of 1999. Under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, NASA's Dryden Flight Research Center assisted Scaled Composites in developing a sophisticated station-keeping autopilot system and a satellite communications (SATCOM)-based uplink-downlink data system for Proteus' performance and payload data. Flight testing included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, was installed and checked out in several flight tests. The systems performed flawlessly during Proteus' deployment to the Paris Airshow in 1999. NASA has used Proteus as a testbed for a variety of technologies related to maturing unmanned air vehicles (UAVs) for use in civil applications. A small Airborne Real-Time Imaging System (ARTIS) camera, developed by HyperSpectral Sciences, Inc., under NASA's ERAST project, was demonstrated during the summer of 1999 when it took visual and near-infrared photos from Proteus while it was flying high over the Experimental Aircraft Association's "AirVenture 99" Airshow at Oshkosh, Wisc. The images were displayed on a computer monitor at the show only moments after they were taken. In March 2002, NASA Dryden, in cooperation with New Mexico State University's Technical Analysis and Applications Center (TAAC), the FAA and several other entities, conducted flight demonstrations of an active detect, see, and avoid (DSA) system for potential application to unmanned aerial vehicles (UAVs) out of Las Cruces, New Mexico. Proteus was flown as a surrogate UAV controlled remotely from the ground, although safety pilots were aboard to handle takeoff and landing and any potential emergencies. Three other aircraft, ranging from general aviation aircraft to a NASA F/A-18, served as "cooperative" target aircraft with an operating transponder. In each of 18 different scenarios, a Goodrich Skywatch HP Traffic Advisory System (TAS) on the Proteus detected approaching air traffic on potential collision courses, including several scenarios with two aircraft approaching from different directions. The remote pilot then directed Proteus to turn, climb or descend as needed to avoid the potential threat. In April 2003, a second series of flight demonstrations focusing on "non-cooperative" aircraft (those without operating transponders), was conducted in restricted airspace near Mojave, Calif., again using the Proteus as a surrogate UAV. Proteus was equipped with a small Amphitech OASys 35 Ghz primary radar system to detect potential intruder aircraft on simulated collision courses. The radar data was telemetered directly to the ground station as well as via an Inmarsat satellite system installed on Proteus. A mix of seven intruder aircraft, ranging from a sailplane to a high-speed jet, flew 20 scenarios over a four-day period, one or two aircraft at a time. In each case, the radar picked up the intruding aircraft at ranges from 2.5 to 6.5 miles, depending on the intruder's radar signature. Proteus' remote pilot on the ground was able to direct Proteus to take evasive action if needed. Based on the preliminary results of both series of tests, project engineers believe that some upgrades would have to be made to both the Skywatch and the OASys detection systems to maximize their effectiveness as collision-avoidance detection sensors for UAVs. Additional flight tests of other types of detection systems, such as electro-optical infrared devices, may occur in the future under a follow-on program in an effort to establish an equivalent level of safety for UAVs to that now required of manned aircraft. The ERAST Project is sponsored by the Office of Aerospace Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center, Edwards, Calif. |
| Photo Date |
March 27, 2003 |
|
Northwest Angle, Minnesota:
…
nasa, nasaimageofthedaygalle
…
Although some maps may make
…
minn_ast_2002139
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-05-19 |
| creator |
NASA -- NASA image created by Jesse Allen, Earth Observatory, using ASTER data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan |
| identifier |
minn_ast_2002139 |
|
Alba Patera
PIA03774
Sol (our sun)
Thermal Emission Imaging Sys
…
| Title |
Alba Patera |
| Original Caption Released with Image |
(Released 22 April 2002) The Science This image, centered near 46.5 N and 119.3 W (240.7 E), is on the northwestern flank of a large, broad shield volcano called Alba Patera. This region of Mars has a number of unique valley features that at first glance look dendritic much in the same pattern that rivers and tributaries form on Earth. A closer look reveals that the valleys are quite discontinuous and must form through a different process than surface runoff of liquid water that is common on Earth. A number of processes might have taken place at some point in the Martian past to form these features. Some of the broad valley features bear some resemblance to karst topography, where material is removed underground by melting or dissolving in groundwater causing the collapse of the surface above it. The long narrow valleys resemble surfaces where groundwater sapping has occurred. Sapping happens when groundwater reaches the surface and causes headward erosion, forming long valleys with fewer tributaries than is seen with valleys formed by surface water runoff. The volcano itself might have been a source of heat and energy, which played a role in producing surfaces that indicate an active groundwater system. The Story Fluid, oozing lava poured somewhat lazily over this area long ago. It happened perhaps thousands of times, over hundreds of thousands of Martian years, creating the nearly smooth, plaster-of-Paris-looking terrain seen today. (Small craters also dent the area, though they may deceive you and look like raised bumps instead. That's just a trick of the eye and the lighting - tilt your head to your left shoulder, and you should see the craters pit the surface as expected.) The lava flows came from a Martian "shield" volcano named Alba Patera. Shield volcanoes get their name from their appearance: from above, they look like large battle shields lying face up to the sky as if a giant, geological warrior had lain them down. Perhaps one did if you think of a volcano as a "geologic warrior," that is. These volcanoes aren't too fierce, however. Because of the gentle layering of lava over time, they don't stand tall and angry against the horizon, but instead have relatively gentle slopes and are spread out over large areas. (On Earth, the Hawaiian Islands are examples of shield volcanoes, but you can't see much of their expanse, since they rise almost three miles from the ocean floor before popping out above the water's surface.) What's most interesting in this picture are all of the branching features that lightly texture the terrain. The patterns may look like those caused by rivers here on Earth, but geologists say that no surface streams on Mars were responsible. That's no disappointment, however, to those who'd like to find water on Mars, because there are still intriguing water-related possibilities here. Some of the broad valley features in this image look like karsts, a terrain found on Earth in Karst, a limestone area on the Adriatic, Sea in modern-day Croatia, and in other world regions including France, China, the American Midwest, Kentucky, and Florida. Karst terrain on Earth is barren land with all kinds of caves, sinkholes, and underground rivers that excavate the subsurface, causing the surface above it to collapse. So, perhaps it's like that in this region on Mars as well. Future Martian spelunkers should be excited, because most caves on Earth are in karst areas. Other suggestions of water here are some long, narrow valleys that resemble Earth surfaces where groundwater has sapped away the terrain. Sapping occurs when groundwater erodes slopes, creating valleys. Water action can be concentrated at valley heads, leading to what is called their "headward growth." That may be what has happened here on Alba Patera as well. All of these features suggest the action of liquid water, but Mars is so cold, you might wonder if any water would have to be as frozen as the world it is on. Well . . . that depends! Remember that this area is part of a volcano, and volcanoes can put out enough heat and energy below the surface to keep water warm enough to flow - if not now, then at least in the past when the volcano was more active. |
|
Alba Patera
PIA03774
Sol (our sun)
Thermal Emission Imaging Sys
…
| Title |
Alba Patera |
| Original Caption Released with Image |
(Released 22 April 2002) The Science This image, centered near 46.5 N and 119.3 W (240.7 E), is on the northwestern flank of a large, broad shield volcano called Alba Patera. This region of Mars has a number of unique valley features that at first glance look dendritic much in the same pattern that rivers and tributaries form on Earth. A closer look reveals that the valleys are quite discontinuous and must form through a different process than surface runoff of liquid water that is common on Earth. A number of processes might have taken place at some point in the Martian past to form these features. Some of the broad valley features bear some resemblance to karst topography, where material is removed underground by melting or dissolving in groundwater causing the collapse of the surface above it. The long narrow valleys resemble surfaces where groundwater sapping has occurred. Sapping happens when groundwater reaches the surface and causes headward erosion, forming long valleys with fewer tributaries than is seen with valleys formed by surface water runoff. The volcano itself might have been a source of heat and energy, which played a role in producing surfaces that indicate an active groundwater system. The Story Fluid, oozing lava poured somewhat lazily over this area long ago. It happened perhaps thousands of times, over hundreds of thousands of Martian years, creating the nearly smooth, plaster-of-Paris-looking terrain seen today. (Small craters also dent the area, though they may deceive you and look like raised bumps instead. That's just a trick of the eye and the lighting - tilt your head to your left shoulder, and you should see the craters pit the surface as expected.) The lava flows came from a Martian "shield" volcano named Alba Patera. Shield volcanoes get their name from their appearance: from above, they look like large battle shields lying face up to the sky as if a giant, geological warrior had lain them down. Perhaps one did if you think of a volcano as a "geologic warrior," that is. These volcanoes aren't too fierce, however. Because of the gentle layering of lava over time, they don't stand tall and angry against the horizon, but instead have relatively gentle slopes and are spread out over large areas. (On Earth, the Hawaiian Islands are examples of shield volcanoes, but you can't see much of their expanse, since they rise almost three miles from the ocean floor before popping out above the water's surface.) What's most interesting in this picture are all of the branching features that lightly texture the terrain. The patterns may look like those caused by rivers here on Earth, but geologists say that no surface streams on Mars were responsible. That's no disappointment, however, to those who'd like to find water on Mars, because there are still intriguing water-related possibilities here. Some of the broad valley features in this image look like karsts, a terrain found on Earth in Karst, a limestone area on the Adriatic, Sea in modern-day Croatia, and in other world regions including France, China, the American Midwest, Kentucky, and Florida. Karst terrain on Earth is barren land with all kinds of caves, sinkholes, and underground rivers that excavate the subsurface, causing the surface above it to collapse. So, perhaps it's like that in this region on Mars as well. Future Martian spelunkers should be excited, because most caves on Earth are in karst areas. Other suggestions of water here are some long, narrow valleys that resemble Earth surfaces where groundwater has sapped away the terrain. Sapping occurs when groundwater erodes slopes, creating valleys. Water action can be concentrated at valley heads, leading to what is called their "headward growth." That may be what has happened here on Alba Patera as well. All of these features suggest the action of liquid water, but Mars is so cold, you might wonder if any water would have to be as frozen as the world it is on. Well . . . that depends! Remember that this area is part of a volcano, and volcanoes can put out enough heat and energy below the surface to keep water warm enough to flow - if not now, then at least in the past when the volcano was more active. |
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