From spencer Mon Dec 11 12:01:27 1995 From spencer Mon Dec 11 12:01:27 1995 To: oleroemer Subject: Galileo Mission Status X-Sun-Charset: US-ASCII Content-Length: 4276 X-Lines: 91 Status: RO From Leslie Tamppari and Terry Martin... Here's a status report and a press release. ________________________________________________________________________________ Galileo Status Report December 8, 1995 Galileo Orbiter is operating normally in dual-spin cruise mode (gyros off, as planned). The Orbiter operated absolutely flawlessly throughout all the planned arrival activities including tape recording fields and particles data in the Io Torus, both tape recording and CDS storage of the Probe relay data and performing a "perfect" JOI. As very recently planned, we have taken advantage of a low altitude Io delivery dispersion that produced an increased gravity-assist that in combination with the virtually nominal JOI resulted in an orbital period one week less than nominal. Acccordingly, the first in-orbit encounter--Ganymede-1--will now occur one week early on June 27th. This strategy enabled us to cancel the first orbit trim (OTM) that was to have been done tomorrow and we also expect to cancel the second OTM scheduled for Jan 2nd. This strategy saves several kg of propellant wrt the current allocations. We are now planning to use the OTM-1 maneuver "window" on Saturday to return from CDS the 75 min of doppler wind data and the first 16 min of the "extended" symbol storage data. (Extended data covers from 40 min to 73 min into the 75 min total Relay Link.) The doppler wind data should tell us how long the signal (Probe) lasted. We plan to give PIO a status statement 5pm Sunday. (See attached below) The only spacecraft "incident" on arrival day was that the star scanner lost attitude reference for 35 min beginning 3 min before relay due to radiation noise. This was a clear vindication of all the work we did to implement Canopus only as first backup and Sun Sensor as second backup to protect the Relay antenna pointing given our concerns that radiation would temporarily defeat the star scanner. ________________________________________________________________________________ PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011 GALILEO MISSION STATUS December 10, 1995 5 p.m. PST Preliminary indications are that NASA's Galileo Jupiter atmospheric probe transmitted its data to the Galileo orbiter mothership for 57 minutes during the probe's suicidal plunge into Jupiter's atmosphere last Thursday, said Project Manager Bill O'Neil. "We are all absolutely ecstatic that our tremendously ambitious, first-ever penetration of an outer planet atmosphere has been so wonderfully successful," said Bill O'Neil, Galileo Project Manager at NASA's Jet Propulsion Laboratory in Pasadena, CA. "It's especially gratifying because so many of us have worked so hard for nearly two decades to get this first true taste of Jupiter's atmosphere." The first scientific results from the probe data are to be presented in a press briefing on December 19th at NASA's Ames Research Center, Mountain View, CA. Ames, supported by Hughes Space and Communications Company, was responsible for the probe development and operations and continues now as the lead NASA center for the analysis of the probe scientific data with Marcie Smith as probe manager and Dr. Rich Young as probe scientist. They are leading a team of about 50 scientists who will interpret the first-ever direct measurements of Jupiter. The Galileo orbiter continues to perform perfectly in orbit around Jupiter, project manager O'Neil said. Given the spacecraft's precise targeting, he said he expects no "orbit trim" adjustments will be required to alter Galileo's orbital path prior to the so-called perijove raise maneuver, the third and last burn of the spacecraft's 400-Newton main engine scheduled for March 1996. That long-planned maneuver is designed to lift Galileo's orbit out of the high-radiation environment of Jupiter's charged-particle belts which could damage the spacecraft's electronics. ##### ----- End Included Message -----