Spaceflight Now: Breaking News

Galileo keeps probing Jovian magnetosphere
Posted: January 16, 2001

This week finds Galileo completing week 12 of a 14-week-long survey of the Jovian magnetosphere. Playback of data stored during the spacecraft's December 2000 passage through the Jupiter system is not scheduled to start until early next month. This is a relatively quiet week with no major activities taking place on the spacecraft.

Galileo's survey data are recorded to its onboard tape recorder five times this week. Typically, these data are almost immediately packaged and transmitted to Earth. However, radio antennas of the Deep Space Network (DSN) are scheduled to listen to Galileo for only about 116 hours (out of a total 168 hours possible in a given week). For the hours during which no DSN coverage is available, the spacecraft makes use of a data buffer (a section of computer memory) to store up to seven hours of survey data at one time. When the buffer is full, and the DSN is not listening, the data are recorded to the tape recorder to prevent data loss.