MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

FOR IMMEDIATE RELEASEDecember 16, 1999

TERRA EARTH SCIENCE MISSION RESET FOR LAUNCH DEC. 18

       The launch of NASA's Earth-observing Terra satellite from Vandenberg Air Force Base, Calif., aboard a Lockheed Martin Atlas IIAS rocket has been tentatively rescheduled for Saturday, Dec. 18, after cancellation of Thurday's launch attempt due to a launch ground-system problem. The launch window for Saturday's attempt is 25 minutes in duration, extending from 10:33 to 10:58 a.m. PST (1:33 to 1:58 p.m. EST).

       Terra bears state-of-the-art instruments, including two managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., to study interactions between the land, atmosphere, ocean and life on the planet.

       Terra, managed by NASA's Goddard Space Flight Center, Greenbelt, Md., is the NASA flagship mission in a new series of spacecraft dedicated to the U.S. Global Change Research Program. Terra carries five sophisticated instruments with measurement and accuracy capabilities never before flown. See http://eos-am.gsfc.nasa.gov for details on the mission.

       Terra takes a global approach to data collection that will enable scientists to study the interaction among the four spheres of the Earth system -- the oceans, lands, atmosphere and biosphere. Long-term weather and climate prediction requires the collection of better data over longer periods to understand the links between these spheres.

       The two instruments managed by JPL are:

       - The JPL-built Multi-angle Imaging Spectro-Radiometer, called MISR, which will improve our understanding of the Earth's ecology and climate by studying how changes in the amounts, types, and distribution of clouds, airborne particulates, and surface covers can affect our climate. See http://www-misr.jpl.nasa.gov for more information.

       - The Advanced Spaceborne Thermal Emission and Reflection Radiometer, called ASTER, a joint U.S.-Japanese instrument, which will produce detailed global, regional and local image maps of land surface temperature, reflectance and elevation and other characteristics. ASTER is the only high-spatial resolution instrument on Terra, and the instrument's ability to serve as a "zoom" lens for the other instruments will be particularly important for land studies, detecting surface changes, and for calibrating instruments. See http://asterweb.jpl.nasa.gov for more information.

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