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(meteorobs) Research Aircraft To Fly Below Leonids
NOTE: The "Once-in-a-Century" claim in the news release needs to be
clarified.
*****
National Science Foundation
Washington, D.C.
Media contact: Cheryl Dybas, NSF (703) 306-1070 cdybas@nsfdot gov
Media contact: Anatta, UCAR Communications (303) 497-8604 anatta@ucardot edu
Program contact: Cliff Jacobs, NSF (703) 306-1521 cjacobs@nsfdot gov
NSF PR 98-74 November 6, 1998
Research Aircraft Fly Below Once-in-a-Century Leonid Meteor Storm
Two research aircraft carrying new scientific observing instruments and high-
definition TV cameras will seize a once-in-a-lifetime opportunity to observe
the Leonids meteor shower on November 17, 1998. Only once a century does
Earth's orbit cross the dense part of the tail of Comet Temple-Tuttle, which
produces the storm.
An L-188C Electra, owned by the National Science Foundation (NSF) and
operated by the National Center for Atmospheric Research (NCAR) in Boulder,
Colo. will be joined by an Air Force KC-135 in the night skies over Okinawa,
Japan, during the meteor storm.
"The NSF Electra is an ideal platform to participate in the Leonids meteor
experiment," says Cliff Jacobs, program manager in NSF's division of
atmospheric sciences, which funds NCAR. "Its ability to accommodate multiple
state-of-the-art, upward-looking instruments will provide an exceptional
opportunity to study these meteors."
The meteor storm will occur when Earth enters the dense debris behind Temple-
Tuttle on November 17, 1998, and again on November 18, 1999. Although the
comet returns every 33 years, its orbit crosses Earth's only once every
hundred years. This century's crossing offers scientists a close look at the
trails of unusually fresh and large (millimeter- to centimeter-size) meteors
entering the earth's atmosphere at the fastest possible speeds -- 72
kilometers per second (160,000 miles per hour). Best observations will be
from East Asia (China and Japan). Next year, Europe and North Africa will
offer the best viewing. From the ground, the source of the storm appears in
the constellation Leo.
The National Aeronautics and Space Administration is heading the experiment,
which is the first mission in NASA's Astrobiology Program, created to study
the origin and prevalence of life in the universe. The Leonid Multi-
Instrument Aircraft Campaign is also supported by NSF, the U.S. Air Force,
and NHK Japanese television.
The two aircraft are needed to take the observing instruments into clear
skies above the weather-laden lower atmosphere. The Air Force's FISTA (Flying
Infrared Signatures Technology Aircraft) will circle the NSF/NCAR Electra in
a racetrack pattern between 30,000 and 40,000 feet while the Electra flies
back and forth (north-south) about 10,000 feet lower within the loop. At
these altitudes (7 to 10 kilometers, or roughly 4 to 6 miles) both planes
will be safe from the meteors above, which will burn up at 100 to 120
kilometers (60 to 75 miles) above the ground.
A major scientific goal of the mission is to determine how a meteor's mass
compares to its brightness. To date, scientists can only guess how much
material enters the atmosphere during a meteor shower. The Electra will
carry a dual-beam lidar (laser-based radar) built this year to detect iron
vaporized from the meteors in the upper atmosphere. Says NCAR project manager
Bruce Morley, "We know very little about iron in the atmosphere and even
less about the iron contribution from meteors. Observing just one meteor
accurately from the sky would make a big difference to our understanding."
-NSF-
Editors: High-resolution color photos of the Electra are available via the
Internet using anonymous ftp: Log on to ftp.ucardot edu, using the userid:
anonymous password: [your e-mail address] directory: /communications
[include the slash] filenames: elecnight1.tif, elecnight2.tif,
elecnight3.tif, elecnight4.tif, and electra.tif
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