This Week On Galileo - August 24-30, 1998
This week Galileo continues on the inbound leg of its orbit around Jupiter, heading towards its next encounter with Jupiter's moon Europa. The encounter is scheduled for late September and will be the sixth of the Galileo Europa Mission. On Monday, the spacecraft executes a small flight path correction. The correction is used to fine tune the spacecraft's orbit as it heads back into the heart of the Jupiter system. Immediately following the flight path correction, flight team controllers will send a command to the spacecraft to pause processing and transmission to Earth of data stored on the spacecraft's tape recorder. This is done to support a real-time observation by the fields and particles instruments of Jupiter's magnetotail region.
During this real-time observation, data is gathered from the fields and particles instruments and placed in an onboard memory buffer for packaging, and is then transmitted to Earth. This buffer is also used for processing and packaging of recorded data. Pausing tape recorder playback gives the real-time data exclusive use of this memory buffer, allowing data acquisition to bridge across all or parts of the gaps that exist in Galileo's Deep Space Network antenna schedule. This, in turn, increases the amount and continuity of magnetospheric data that can be returned to Earth successfully.
Jupiter's magnetosphere is defined as that part of space where Jupiter's magnetic field dominates the magnetic field of the solar wind. The magnetotail is the part of the magnetosphere that has been "pushed" into a long, streaming tail by the solar wind. Studies of this region were conducted about one year ago, during Galileo's primary mission, to understand how the magnetotail evolves and interacts with the middle and inner portions of the magnetosphere, and with the solar wind. The information obtained during this year's real-time observation will help identify changes in the magnetosphere over the period of the last year, and will add to the understanding of how plasma escapes from the inner portions of the magnetosphere.
The fields and particles observation actually spans several weeks. It started about a week ago and will continue into September. This week's tape recorder playback interruption provides enhanced data gathering during a time of great interest. Additional playback interruptions are under consideration, but may be hampered by the need to perform other spacecraft operations. Stay tuned!