PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 9ll09. TELEPHONE (213) 354-5011
FOR IMMEDIATE RELEASE

       More than 50,000 photographs of Mars taken by NASA's Viking orbiters from l976 through l980 have been processed at the Jet Propulsion Laboratory.

       The last photographs taken by Viking Orbiter through the summer of l980 were processed in late March this year. The orbiter, one of two that arrived at Mars in l976, was turned off in August l980, after it ran out of attitude control gas. Viking 2 Orbiter ceased operations in July l978. The Viking Lander continues to return scientific data, including photographs, from the Mars surface. The Viking 2 Lander ceased operating in April l980.

       The surviving lander, which is beginning its fourth Martian year of surface and climate studies, is sending back valuable imaging, engineering and meteorological data weekly. Jim Tillman, of the University of Washington, is computer processing this science and engineering data. The lander's radio science investigations also continue.

       A program is currently underway onboard Lander which reconditions each of its four batteries. Barring any critical hardware failures, the lander can continue to operate until Dec. 5, l994.

       Scientists at JPL and other research centers across the country continue to study the Mars imaging data. Work at JPL includes mosaicking the orbiter images, and the study of channels, volcanoes and tectonic features on the Martian surface. Results, reported from analysis of photos and other data, indicate strong evidence that surface water exists on Mars in the form of ground ice.

       In addition, the layers in the north polar cap appear to hold the key to understanding the climate changes on that planet as they do on Earth. Finally, the seasonal nature of Mars can be noted in cloud forms and motion, volatile migration from pole to pole, frost accumulation, and variations in temperature and pressure.

       The landers were built by Martin Marietta Aerospace Corp. in Denver, Colorado. JPL developed and built the orbiters.

       Viking l, launched on Aug. 20, l975, arrived at Mars on June l9, l976. The Viking Lander separated from the orbiter and landed in the Chryse Planitia region on Mars on July 20, l976.

       Viking 2 was launched on September 9, l975 and entered orbit around Mars on August 7, l976. The Viking 2 Lander landed in the Utopia Planitia region of the planet on Sept. 3, l976.

       The extended Viking Mission is managed for NASA by JPL.

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4/22/82 MBM
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