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

Contact: James H. Wilson

FOR IMMEDIATE RELEASE                                                                                                October 8, 1991


       NASA's Galileo spacecraft received computer sequence commands on Monday, October 7, to perform its trajectory correction maneuver for the first asteroid flyby.

       The maneuver, scheduled to start at 1656 Universal Time (Earth received time 10:17 a.m. PDT) on Wednesday, will change the spacecraft velocity by less than one mile per hour to bring it on target for the encounter with the asteroid Gaspra on October 29. This maneuver is based on optical navigation, data obtained with Galileo's camera, as well as radio tracking data. The mission sequence includes opportunities for additional fine adjustments if needed.

       Galileo is now 231 million miles from Earth and 201 million miles from the Sun; its speed in orbit is more than 36,000 miles per hour.

       Pictures of the asteroid and other scientific data will be stored in the spacecraft tape recorder for playback to Earth either when Galileo's high-gain antenna becomes available or when the spacecraft again approaches Earth in November 1992, as currently planned. This data transmission procedure was used after Galileo's February 1990 encounter with Venus.

       The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory.


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10/8/91 JHW
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