Christmas on Galileo December 18-26, 2000
During the next nine days, Galileo completes week eight of a 14-week long survey of the Jovian magnetosphere. Past the half-way point of the survey, Galileo also prepares for its next close encounter with the Jupiter system. On Thursday, December 28, the spacecraft will fly just short of 2,500 kilometers (1,550 miles) from the surface of Ganymede. Preparations for the flyby include a small flight path adjustment performed on Thursday, December 21, and standard maintenance on the spacecraft’s onboard tape recorder on Monday, December 25.
The December 28 flyby will bring to a close Galileo’s longest and largest orbit around Jupiter since arrival at Jupiter in December 1995. Lasting 222 days, the spacecraft’s flight path took it to a distance of 290 Jupiter radii (20.7 million kilometers, or 12.9 million miles) from Jupiter on September 8, 2000. Galileo’s second largest orbit followed immediately after arrival when the spacecraft traveled for 203 days between encounters and reached a maximum range of 270 Jupiter radii (19.3 million kilometers, or 12.0 million miles).
The survey of the Jovian magnetosphere is being performed by Galileo’s Fields and Particles instruments, and is part of a joint observation campaign with the Cassini spacecraft. Cassini’s flight plan takes it by Jupiter on December 30, en route to Saturn in 2004. Joint Galileo and Cassini observation campaigns are planned during the days and weeks surrounding the dual-spacecraft encounter with Jupiter and its moons. The joint flyby will offer scientists a unique opportunity to examine data describing the Jupiter system as viewed from two different observation platforms, a very rare event.
Come back on Wednesday, December 27, for the return of Today on Galileo and the excitement of another Galileo encounter. Until then, the Galileo Project wishes you and yours a very happy holiday season!
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:
http://galileo.jpl.nasa.gov
http://www.jpl.nasa.gov/galileo
