From: Jet Propulsion Laboratory
Posted: Monday, November 26, 2001
This week's major spacecraft activity comes on Friday, when Galileo performs an orbit trim maneuver. This is the second of three rocket engine burns planned to occur between the 32nd and 33rd close satellite encounters since the aging spacecraft went into orbit. This one is scheduled to take place near apojove, or the farthest point in the orbit from the giant planet Jupiter. Apojove occurs on Saturday, at about 1:30 p.m. PST, when the distance from Galileo to Jupiter is 160.9 of Jupiter's radii. This translates into 11.5 million kilometers, or 7.15 million miles, which is fully 1/13 the distance from the Earth to the Sun.
This is not the farthest from Jupiter that the spacecraft has been since first arriving in orbit in December 1995. That honor goes to the 28th orbit, when we reached a distance of nearly 290 Jupiter radii (20.7 million kilometers or 12.9 million miles). But that distance in turn will be surpassed in our 34th orbit in April 2003 when we stretch out to 369.5 Jupiter radii (26.4 million kilometers or 16.4 million miles) before making our final plunge into Jupiter's atmosphere in September.
The remainder of the week is filled with the steady collection of real-time data by the Magnetometer, the Dust Detector, and the Extreme Ultraviolet Spectrometer, and by the continued playback of recorded data from the October 15 flyby of Io.
While the Fields and Particles instruments continue the return of a 1.5-hour recording centered on the closest approach of Galileo to Io, the Near Infrared Mapping Spectrometer (NIMS) and the Solid State Imaging camera (SSI) play back data also acquired when Galileo was near its closest point to Io. NIMS observations will provide thermal mapping and sulfur dioxide distribution around Emakong caldera (an extended volcanic crater), Tupan Patera (an active volcanic site that displays distinctive red deposits), and Chaac caldera. An additional observation will examine a newly discovered hot spot.
SSI will return pictures of Tohil Mons and Patera, the Mycenae Regio, Culann Patera, and a region near the giant volcano Prometheus, taken while those features were near the terminator, or day-night boundary. Additional views are of the Gish Bar hot spot and a color look at the active volcanic patera Tupan. SSI will also return the first medium-resolution look at the Tvashtar volcanic region since a large plume eruption occurred there in late 2000.
For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at one of the following URL's:
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