PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

Contact: Jim Doyle

FOR IMMEDIATE RELEASE                                                September 27, 1991

       With more than 90 percent of Venus now mapped by the Magellan spacecraft, Earth's nearest planetary neighbor is described as a planet of searing winds, violent crustal deformations and giant volcanic eruptions.

       Dr. Steve Saunders, the Magellan Project Scientist at NASA's Jet Propulsion Laboratory, said the planet's volatility becomes increasingly evident, and Magellan's imaging radar system is particularly well-suited to unveiling its mysteries.

       Magellan has orbited Venus 3,152 times over the past 377 days.

       Of those orbits, 2,662 were mapping orbits and to date Magellan has mapped 90.1 percent of the surface. The second cycle coverage, which began May 16, has overlapped 26.4 percent of the first cycle mapping.

       Dr. Stephen Saunders, the project scientist, said that Venus is even more torn by tectonic forces than had been thought before the Magellan mapping began.

       The spacecraft recently has completed the first look at the western area of the continent-sized uplands called Ishtar Terra. The plains-like area, named Lakshmi Planum, is elevated about two miles above the average elevation of Venus. Lakshmi is surrounded by mountains that have been pushed up on all sides, including the 36,000-foot high Maxwell Mountains.

       Scientists are studying images made during the recent observation. One shows mosaics of mountains belts on the west and south sides of Lakshmi Planum, the Akna and Danu mountains.

       The image also shows an impact crater, named Wanda, which appears to have been made after the Akna mountains formed. The western ridge of the crater has collapsed onto its floor.

       Another image shows the Danu mountains to the south of the plains and a circular volcanic dome 12 miles in diameter. The southern part of the dome has been deformed by the tectonic processes which created the mountains.


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9/26/91 JJD
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