Galileo Mission Status - Novmeber 11, 1997
PUBLIC INFORMATION 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
NASA's Galileo spacecraft has successfully completed its latest flyby of Europa, with closest approach occurring last Thursday, Nov. 6, at an altitude of 2,043 kilometers (1,269 miles). The signal reached Earth at 1:13 p.m. PST. All systems on the spacecraft performed flawlessly.
About six minutes before closest approach, a glitch appeared in the azimuth slewing lubrication system of the DSS-63 antenna at the Deep Space Network tracking station in Madrid, Spain. This caused a temporary pause in communications with the spacecraft. However, about five minutes after closest approach, the signal was acquired by the DSS-14 antenna in Goldstone, CA. Although the temporary outage caused a loss of some radio science tracking data, the radio science team anticipates many additional opportunities to conduct their experiments during the eight consecutive Europa flybys planned for Galileo's extended mission. Thursday's encounter was the final flyby of the primary mission, but the extended mission -- called the Galileo Europa Mission, or GEM -- begins next month and continues through December 1999. In addition to the eight Europa flybys, GEM will include four Callisto flybys and one or two close flybys of Io, depending on spacecraft health.
Galileo is now transmitting to Earth pictures and other information gathered during the Nov. 6 Europa flyby. Europa images include observations of "hot" regions on the icy satellite's surface, as well as wedge-shaped dark bands, the craters Pwyll and Mannann'an, and features known as triple bands and bright plains.
The spacecraft's playback schedule is paused twice this week - once today for regular propulsion system maintenance, and again beginning on Saturday night, Nov. 15, when Jupiter will block the signal between Earth and the Galileo spacecraft for 15 hours. This planetary alignment, called an Earth occultation, will enable radio scientists to analyze Jupiter's atmosphere by measuring changes in Galileo's radio signal as it passes through the Jovian atmosphere.
Much of this week's data return includes Jupiter observations, including those designed to study brown barges, believed to contain a unique mixture of chemicals. Other observations are designed to create a cylindrical map of a large portion of Jupiter's atmosphere. The playback schedule also includes an observation of Io performed by the solid state imaging camera when the fiery moon was blocked from the Sun by Jupiter. These are very powerful images for studying Io's spots and volcanic activity.
Return to Project Galileo Homepage