> Contacts: NASA Headquarters/Dolores Beasley 202-358-1753 > JPL/Martha Heil 818-354-0850 > > FOR IMMEDIATE RELEASE November 14, 2001 > > NASA LEONIDS ACTIVITIES: SLEEPYHEADS MAY MISS SPECTACULAR CELESTIAL DISPLAY > > Early birds may catch more than their proverbial worms > this week. In the predawn hours of Sunday, Nov.18, the annual > Leonid meteor shower may put on one of its best shows in > decades, according to various scientists modeling the expected > Leonid activity this year. > > "It's time to set your alarm clocks and get yourself out > under a dark sky," said Dr. Donald Yeomans, head of NASA's > Near Earth Object program office, at the Jet Propulsion > Laboratory, Pasadena, Calif. "This could be the last > opportunity for watching an impressive meteor storm in a dark > sky for decades to come." > > Yeomans explains what the Leonids are and how to see > them, in a video on the JPL Web site at: > http://www.jpl.nasa.gov . > > Meteors, also called shooting stars, are really streaks > of light that flash across the sky as bits of dust and rock in > space collide with Earth's upper atmosphere and vaporize. The > Leonid shower appears every year around Nov. 17 or 18 as the > Earth intersects the orbit of comet Tempel-Tuttle and runs > into streams of dust shed by the comet. Best viewing times > this year are predicted to be the early morning hours of > November 18, with the peak activity expected around 2 a.m. PST > (5 a.m. EST). > > They are called Leonid meteors for the direction in the > sky from which they appear to originate -- the constellation > Leo. Because the stream of comet dust hits Earth almost head- > on, the Leonids are among the fastest meteors around -- they > zip silently across the sky at nearly 70 kilometers per second > (44 miles per second). Every so often, Earth passes through an > especially dense clump of dust from Tempel-Tuttle, and a truly > spectacular meteor storm occurs -- the great Leonid storm of > 1966 produced 150,000 meteors per hour. > > Four NASA centers -- JPL; Marshall Space Flight Center, > Huntsville, Ala.; Goddard Space Flight Center, Greenbelt, Md.; > and the Ames Research Center, Moffett Field, Calif. -- have > activities scheduled around this year's meteor shower. > > At Marshall, researchers will use special cameras to scan > the skies and report meteor activity around the clock Nov. 17 > and 18. From six key points on the globe, they will record and > transmit their observations to Marshall's Leonid Environment > Operations Center, a data clearinghouse that will provide > meteor updates in near real-time through > http://www.SpaceWeather.com -- a Web site sponsored by > firstname.lastname@example.org. > > "We're collecting this data to analyze and refine our > meteor-forecasting techniques," said Dr. Rob Suggs, the Leonid > Environment Operations Center team leader. "If we can better > determine where, when and how the meteors will strike, we can > take protective measures to prevent or minimize damage to our > spacecraft." > > The researchers, along with colleagues from the > University of Western Ontario in Canada and the U.S. Air > Force, will monitor the storm from six locations, Huntsville, > Ala.; Eglin Air Force Base, Fla.; Maui, Hawaii; Sunspot, N.M.; > the U.S. Territory of Guam; and the Gobi Dessert in Mongolia. > Each location was selected based on meteor forecasts and the > area's climate. > > The monitoring team also has the capability to detect > meteors the casual observer may miss. Using special image- > intensified cameras that can detect faint objects even in low- > light conditions, the researchers will monitor the shower, > using the video screens as windows to the skies. Every hour, > the teams will relay their observations to the Marshall > control center, helping to paint a comprehensive picture of > the meteor storm. > > Most Leonid particles are the size of dust grains, and > will vaporize very high in the atmosphere, so they present no > threat to people on the ground or even in airplanes. However, > there is a slight chance that a satellite could be damaged if > it were hit by a Leonid meteor. The meteors are too small to > simply blow up a satellite. However, the Leonids are moving so > fast they vaporize on impact, forming a cloud of electrified > gas called plasma. Since plasma can carry an electric current, > there is a risk that a Leonid-generated plasma cloud could > cause a short circuit in a satellite, damaging sensitive > electronic components. > > Goddard Space Flight Center is responsible for > controlling many satellites for NASA and other organizations > and is taking precautions to mitigate the risk posed by the > Leonids. These include pointing instrument apertures away > from the direction of the Leonid stream, closing the doors on > instruments where possible, turning down high voltages on > systems to prevent the risk of a short circuit, and > positioning satellites to minimize the cross-section exposed > to the Leonids. > > Goddard controls or manages 21 satellites in the earth > and space sciences. It also manages NASA's Tracking and Data > Relay Satellite System constellation, which is controlled from > White Sands, N.M. > > At Ames, meteor experts Dr. David Morrison, chief > scientist at NASA's Astrobiology Institute, and Dr. Scott > Sanford, a NASA planetary scientist, will be available Friday, > Nov. 16, at Ames for media interviews about the Leonid meteor > storm. The scientists will discuss NASA's airborne mission to > study the Leonids, the danger the meteors could pose to > satellites, recent Leonid prediction models and the latest > research, which suggests that meteors may have played a role > in the origin of life. > > On Nov. 18, a team of 19 astrobiologists from five > countries will depart from southern California's Edwards Air > Force Base on an NKC-135 research aircraft to keep an eye on > the sky for satellite operators and to study the processes > that may have jump-started life on Earth. The 418th Flight > Test Squadron at Edwards Air Force Base operates the research > aircraft, which flew previous Leonid Multi-instrument Airborne > Campaign missions in 1998 and 1999 over Japan and Europe. > > Many scientists think meteors might have showered the > Earth with the molecules necessary for life's origin. "We are > eager to get another chance to find clues to the puzzling > question of 'What happens to the organic matter brought in by > the meteoroids?'" said Dr. Michael Meyer, lead scientist for > astrobiology at NASA Headquarters, Washington, D.C. which is > sponsoring the airborne observing mission. > > Astrobiology is the study of the origin, evolution, > distribution and future of life in the universe. Ames is > NASA's lead center for astrobiology and the location of the > central offices of the NASA Astrobiology Institute, an > international research consortium. > > Information about the Leonid Multi-instrument Airborne > Campaign and live Leonid coverage are available at: > http://leonid.arc.nasa.gov/ or > http://www-space.arc.nasa.gov/~leonid/ . > > Observers can calculate local meteor rates using their > home computers via: > http://www.space.arc.nasa.gov/~leonid/fluxestimator.html . > > NASA TV will broadcast live commentary and video of the > Leonids from 9:30 a.m. to 3 a.m. PST (12:30 a.m. to 6 a.m. > EST) Sunday, Nov. 18. The broadcast, originating from > Marshall, will feature live video of the Leonids meteor shower > provided by a video camera with enhanced images and animation. > If weather and cloud cover inhibit observation, the broadcast > will be cancelled and regular programming resumed. > > JPL is managed for NASA's Office of Space Science, > Washington, D.C., by the California Institute of Technology in > Pasadena. > > NOTE TO EDITORS: More information on Leonids activities at > specific NASA Centers is available from: Martha Heil, JPL, at: > 818/354-0850; Steve Roy, Marshall Space Flight Center, at: > 256/544-6535; Bill Steigerwald, Goddard Space Flight Center, > at: 301/286-5017; Kathleen Burton, Ames Research Center, at: > 650/604-1731;. > > # # # # # > 11/14/01 JP > 2001-219 > > --------------------------------------------------------------- > You are subscribed to JPL's news mailing list.
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