Unique Space Image of Alabama Tornado Tracks

May 16, 2011: NASA has released a unique satellite image tracing the damage of a monster EF-4 tornado that tore through Tuscaloosa, Alabama, on April 27th. It combines visible and infrared data to reveal damage unseen in conventional photographs. "This is the first time we've used the ASTER instrument to track the wake of a super-outbreak of tornadoes," says NASA meteorologist Gary Jedlovec of the Marshall Space Flight Center in Huntsville, AL. An ASTER visible-IR image of tornado damage near Tuscaloosa, AL. [larger image] In the picture, captured just days after the storm, pink represents vegetation and aqua is the absence of vegetation. The tornado ripped up everything in its path, scouring the Earth's surface with its terrible force. The "tearing up" of vegetation makes the tornado's track stand out as a wide swath of aqua. "This image and others like it are helping us study the torn landscape to determine just how huge and powerful these twisters were and to assess the damage they inflicted," says Jedlovec. ASTER, short for Advanced Spaceborne Thermal Emission and Reflection Radiometer, orbits Earth onboard NASA's Terra spacecraft. Its data products include digital elevation maps from stereo images; surface temperatures; vegetation maps; cloud and sea ice data; and more. Last spring the instrument helped track the movement of the oil spill in the Gulf of Mexico. Ground survey teams have a lot to contend with. [Youtube video] To detect the scars left by the twisters, ASTER senses the visible and infrared energy reflected from the planet's surface. Destruction like crushed houses, torn and snapped trees, and uprooted crops are evident in the multi-wavelength images. "A demolished house, debris and soil scattered on vegetated surfaces, and damaged trees and crops all change the pattern of reflected radiation measured by the satellite," explains Jedlovec. "We can analyze these patterns to help storm survey teams evaluate the damage." Ground teams conducting field surveys of tornado damage must try to pinpoint where the twisters touched down, how long they stayed on the ground, and the force of their winds. But doing this from ground level can be tricky. Some places are nearly impossible to reach by foot or car. Also, in remote areas, damage often goes unreported, so survey teams don't know to look there. This is where satellites can help. "To get an accurate picture survey teams need to look everywhere that sustained damage – even unreported areas. Satellite sensors detect damage in rural areas, wilderness areas, and other unpopulated areas. Only with that knowledge can surveyors determine the true track of a tornado." Otherwise, says Jedlovec, a twister could have flattened a single dwelling in a remote location, killing everyone inside, and no one would know. Another sample of ASTER tornado data showing three nearly-parallel tracks of destruction. [large image] [annotated composite image] Less critical but still important are home owners' insurance issues. To evaluate claims submitted by storm victims, insurance companies rely on National Weather Service storm reports based on the field surveys. "Let's say you live in a remote area," says Jedlovec. "If there's no record of a storm passing over your area, you could be out of luck." Jedlovec and colleagues are working now to produce satellite images of other areas ravaged by the historic outbreak of tornadoes. "We want to help the storm victims any way we can."

Unique Space Image of Alabama Tornado Tracks

Unique Space Image of Alabama Tornado Tracks May 16, 2011: NASA has released a unique satellite image tracing the damage of a monster EF-4 tornado that tore through Tuscaloosa, Alabama, on April 27th. It combines visible and infrared data to reveal damage unseen in conventional photographs. "This is the first time we've used the ASTER instrument to track the wake of a super-outbreak of tornadoes," says NASA meteorologist Gary Jedlovec of the Marshall Space Flight Center in Huntsville, AL. An ASTER visible-IR image of tornado damage near Tuscaloosa, AL. [larger image] In the picture, captured just days after the storm, pink represents vegetation and aqua is the absence of vegetation. The tornado ripped up everything in its path, scouring the Earth's surface with its terrible force. The "tearing up" of vegetation makes the tornado's track stand out as a wide swath of aqua. "This image and others like it are helping us study the torn landscape to determine just how huge and powerful these twisters were and to assess the damage they inflicted," says Jedlovec. ASTER, short for Advanced Spaceborne Thermal Emission and Reflection Radiometer, orbits Earth onboard NASA's Terra spacecraft. Its data products include digital elevation maps from stereo images; surface temperatures; vegetation maps; cloud and sea ice data; and more. Last spring the instrument helped track the movement of the oil spill in the Gulf of Mexico. Ground survey teams have a lot to contend with. [Youtube video] To detect the scars left by the twisters, ASTER senses the visible and infrared energy reflected from the planet's surface. Destruction like crushed houses, torn and snapped trees, and uprooted crops are evident in the multi-wavelength images. "A demolished house, debris and soil scattered on vegetated surfaces, and damaged trees and crops all change the pattern of reflected radiation measured by the satellite," explains Jedlovec. "We can analyze these patterns to help storm survey teams evaluate the damage." Ground teams conducting field surveys of tornado damage must try to pinpoint where the twisters touched down, how long they stayed on the ground, and the force of their winds. But doing this from ground level can be tricky. Some places are nearly impossible to reach by foot or car. Also, in remote areas, damage often goes unreported, so survey teams don't know to look there. This is where satellites can help. "To get an accurate picture survey teams need to look everywhere that sustained damage – even unreported areas. Satellite sensors detect damage in rural areas, wilderness areas, and other unpopulated areas. Only with that knowledge can surveyors determine the true track of a tornado." Otherwise, says Jedlovec, a twister could have flattened a single dwelling in a remote location, killing everyone inside, and no one would know. Another sample of ASTER tornado data showing three nearly-parallel tracks of destruction. [large image] [annotated composite image] Less critical but still important are home owners' insurance issues. To evaluate claims submitted by storm victims, insurance companies rely on National Weather Service storm reports based on the field surveys. "Let's say you live in a remote area," says Jedlovec. "If there's no record of a storm passing over your area, you could be out of luck." Jedlovec and colleagues are working now to produce satellite images of other areas ravaged by the historic outbreak of tornadoes. "We want to help the storm victims any way we can."

Local Scientists Produce First Aerogel in Space

First Space-Produced Aerogel Made on Space Sciences Laboratory Rocket Flight June 19, 1996: Aerogel is the lightest solid known to mankind, with only three times the density of air. A block the size of a human weighs less than a pound. Because of its amazing insulating properties, an inch-thick slab can safely shield the human hand from the heat of a blowtorch. A sugar-cubed size portion of the material has the internal surface area of a basketball court. As the only known transparent insulator, Aerogel is a supercritically dried gel sometimes referred to as "frozen smoke". On April 3, 1996, the first space-produced samples of aerogels were produced by NASA on a flight of a starfire rocket. The production of such materials in space is interesting because of the strong influence of gravity on how a gel is formed. Comparison of gels manufactured in space and on the ground have shown large differences, and the production of gels in space can provide a higher-quality product with a more uniform structure. Chemical Engineering Progress (June 1995, p 14) described "the holy grail of aerogel applications has been developing invisible insulation for use between window panes." The production of insulating and transparent windows through aerogel manufacturing in space can develop into a substantial market for residential and commercial applications. The excellent thermal properties and transparent nature of silica aerogel make it an obvious choice for super-insulating windows, skylights, solar collector covers, and specialty windows.

Space Sciences Laboratory Hosts Bill Nye, the Science Guy

October 16, 1996 This week, the Marshall Space Flight Center and the Space Sciences Laboratory are hosting Bill Nye, The Science Guy, as their crew from Seattle films for an upcoming episode of the PBS television series. Taping in SSL will occur on Wednesday, October 16 and Thursday, October 17. Areas of science from the laboratory that will be featured on an upcoming episode of Bill Nye include Aerogel, "cool telescopes" such as BATSE and the AXAF Calibration Facility, the SSL Solar Vector Magnetograph, and the 105-meter drop tube for microgravity experimentation. The program will also feature a dive in the Marshall Neutral Buoyancy Simulator, the large tank in which the Hubble Space Telescope repair missions are rehearsed by astronauts, as well as a visit to the Space Station Assembly facility.

First Space-Produced Aerogel Made on Space Sciences Laboratory Rocket Flight

October 8, 1996: Results are now beginning to become available from the April 3, 1996 rocket flight to produce the first space-made Aerogel. As described in the June 19, 1996 Aerogel Headline , Aerogel is the lightest solid known to mankind, with only three times the density of air. Aerogel, because of its appearence is sometimes referred to as "frozen smoke". Aerogel produced on the ground typically displays a blue haze or has a slight cloudiness to its appearence. This feature is believed to be caused by impurities and variations in the size of small pores in the Aerogel material. Scientists are trying to eliminate this haze so that the insulator might be used in window panes and other applications where transparency is important. The Aerogel made aboard the flight of the Starfire Rocket in April has indicated that gravity effects in samples of the material made on the ground may be responsible for the adverse pore sizes and thus account for the lack of transparency. Both the diameter and volume of the pores in the space-made Aerogel appear to be between 4 and 5 times better than otherwise identically formulated ground samples. Because Aerogels are the only known transparent insulator, with typical heat conduction properties that are five times better than the next best alternative, a number of novel applications are foreseen in high performance Aerogels.

Fall Science Meeting Highlights Tethered Satellite Results

October 15, 1996 Scientists attending the Fall 1996 meeting of the American Geophysical Union will be treated to three special sessions covering scientific results obtained from the reflight of the Tethered Satellite System (TSS-1R). The conference will take place on December 18 and 19 in San Francisco, California. The TSS-1R science mission was conducted on space shuttle flight STS-75 at the end of February 1996. During the flight, the Tethered Satellite was deployed to a distance of 12.3 miles (19.7 km) and science data was collected aboard the satellite, the space-shuttle orbiter, and from a network of ground stations monitoring the earth's ionosphere. Five hours of tethered operation yielded a rich scientific data set. These data include tether current and voltage measurements, plasma particle and wave measurements, and visual observations for a variety of pre-planned science objectives. During the flight the conducting tether connecting the Orbiter to the satellite was severed, and large currents were observed to be flowing between the satellite and the Orbiter during the break event. Further scientific data were obtained from the instruments on the satellite after the break, when the science and NASA support teams were able to capture telemetry from the satellite during the overflight of NASA tracking stations. One important finding from TSS-1R has been the high level of current collected by the satellite at relatively low voltage throughout the deployed phase of the mission. Surprisingly large currents were also observed during the tether break and gas releases, indicating important new physics at play. The three Tethered Satellite sessions at the AGU meeting will cover the results of data analysis from the mission, important supporting physics insights from laboratory experiments, theoretical and numerical modeling of current collection during the mission, and the conclusions of recent studies on the future use of tethers for science in space.

Unique telescope to open the X(-ray) Files

Artist's concept of AXAF in orbit., The nested mirrors are at center behind the dotted circles. The finest set of mirrors ever built for X-ray astronomy has arrived at NASA's Marshall Space Flight Center for several weeks of calibration before being assembled into a telescope for launch in late 1998. The High-Resolution Mirror Assembly (HRMA), as it is known, will be the heart of the Advanced X-ray Astrophysics Facility (AXAF) which is managed by Marshall Space Flight Center. HRMA was built by Eastman Kodak and Hughes Danbury Optical Systems. In 1997-98, they will be assembled by TRW Defense and Space Systems into the AXAF spacecraft. AXAF is designed to give astronomers as clear a view of the universe in X-rays as they now have in visible light through the Hubble Space Telescope. Indeed, one of the Hubble's recent discoveries may move near the top of the list of things to do for AXAF. Hubble recently discovered that some quasars reside within quite ordinary galaxies. Quasars (quasi-stellar objects) are unusually energetic objects which emit up to 1,000 times as much energy as an entire galaxy, but from a volume about the size of our solar system. More clues to what is happening inside quasars may lie in the X-rays emitted by the most violent forces in the universe. Before AXAF can embark on that mission, though, its mirrors must be measured with great precision so astronomers will know the exact shape and quality of the mirrors. Then, once the telescope is in space, they will be able to tell when they discover unusual objects, and be able to measure exactly how unusual. These measurements will be done in Marshall's X-ray Calibration Facility, the world's largest, over the next few weeks. AXAF will use four sets of mirrors, each set nested inside the other, to focus X-rays by grazing incidence reflection, the same principle that makes sunlight glare off clear windshields. AXAF's smallest mirror - 63 cm (24.8 in.) in diameter - is larger than the biggest - 58 cm (22.8 in.) flown on the Einstein observatory (HEAO-2) in 1978-81. Mapping the details of the mirror will start with an X-ray source pretty much like what a dentist uses to check your teeth. But that's next week's story.