December 13 - 19, 1999
Galileo Continues to Return Images and Other Science Information from November 25th Flyby of Io
Galileo continues to return images and other science information acquired during a flyby of Jupiter's volcanic moon Io on November 25. Observations taken during this flyby are stored on Galileo's onboard tape recorder, and are being played back to Earth throughout December.
Galileo passes the halfway point of this orbit as it flies through apojove on Wednesday, December 15. Apojove is the point at which the spacecraft is farthest from Jupiter in a given orbit. With this week's playback, Galileo starts a second pass through the observations stored on the tape recorder. This pass allows replay of data lost in transmission to Earth, reprocessing of data using different parameters, or return of additional new data. Playback is interrupted twice this week. On Tuesday, the spacecraft performs a flight path adjustment. On Saturday, the spacecraft performs standard maintenance on its tape recorder.
The Solid-State Imaging camera returns three observations of Io this week. The Emakong Patera volcanic region is returned in the first observation. Scientists hope to see active lava flowing from the hot Emakong caldera. The second observation contains two unnamed giant volcanic calderas in Io's northern hemisphere. The Near-Infrared Mapping Spectrometer also returns an observation of these two features. Finally, the camera returns some portions of a color mosaic of the Culann volcanic region.