Genesis Mission Status Update August 21, 2002

A solar wind shock this week provided the opportunity for
successfully using a software patch that was previously installed
for autonomous recovery of the solar wind concentrator’s
rejection grid when voltage climbs too high. The rejection grid
of fine wires carries a positive charge to deflect hydrogen
ions in the solar wind, so that the solar wind sample being
collected will have a relatively high proportion of the more
scientifically interesting oxygen ions. The shock reached the
spacecraft on Aug. 18, and the rejection grid’s voltage quickly
rose from about 1,000 volts to about 2,000 volts. When a fault
occurred at about 2,025 volts, the software patch successfully
went to work. The rejection grid was autonomously brought down to
1,400 volts, paused for 1 hour, and then ramped up again, ending
at about 1,950 volts.

Another highlight of the week was approval of an improvement in
the flight software for the sample return capsule’s avionics unit.