This Week on Galileo: Four Weeks
20 May 2002
(Source: Jet Propulsion Laboratory)
May 20 - June 16, 2002
The Galileo spacecraft proceeds in its measured pace around the giant planet Jupiter while the flight team continues to diagnose a problem with the on-board tape recorder. On April 12, during a routine maintenance activity, the tape appears to have stuck to the record or playback heads. Four tests have been performed to characterize the problem. On Wednesday, May 22, one final low-speed test will be executed. Based on these results, our efforts will now become more aggressive, possibly trying to move the tape at higher speeds, which should provide more "oomph" to pulling the tape free. Detailed plans for the subsequent tests have not been scheduled as yet, and in the meantime all regularly scheduled tape activities have been put on hold until we have demonstrated that the machine is working properly again.
On Saturday, May 25, the spacecraft performs a 4 degree turn in place to keep the communications antenna pointed towards Earth.
On Friday, May 31, routine maintenance of the propulsion system is performed.
On Monday, June 3, the fourth planned load of sequence commands takes over control of the spacecraft, and will govern Galileo's activities until mid-August.
On Wednesday, June 5, a test of the on-board gyroscopes will be performed. These gyros have shown sensitivity to the intense radiation environment seen near Jupiter, but gradually correct themselves with time spent in the more benign environment far from the planet. This calibration will determine the health of the gyros in preparation for an orbit trim maneuver planned for Friday, June 14. This propulsive engine burn takes place one day after apojove, the farthest point in Galileo's orbit from Jupiter. This is the most distant that Galileo has been from Jupiter since before arriving in orbit in December 1995. At 348.1 Jupiter radii from the planet (24.9 million kilometers or 15.5 million miles) this is approximately one sixth of the distance from Earth to the Sun, and it takes light nearly a minute and a half to speed from Jupiter to the spacecraft!
With the spacecraft well outside the magnetosphere of Jupiter on the sunward side of the planet, continuous data collection by the Magnetometer, the Dust Detector, and the Extreme Ultraviolet Spectrometer instruments provides scientists with information about the interplanetary medium.