spacetoday.net: Galileo goes into safe mode during Io flyby

Posted: Thu, Jan 17, 2002, 6:06 PM ET (2306 GMT)
Galileo at Jupiter illustration

NASA's Galileo spacecraft went into safe mode during its close flyby of Jupiter's moon Io Thursday, disrupting observations of the moon. Project officials said in a status report late Thursday that the spacecraft went into standby, or safe, mode at 8:41 am EST (1341 GMT) Thursday, about a half hour before its closest approach to the volcanic moon. The safe mode was likely triggered by a radiation-induced computer upset, as was the case for several similar problems Galileo encountered earlier in its mission. Engineers believe they will be able to restore the spacecraft to normal operations and return what data it recorded, but the safe mode meant that scientists missed out on the final chance for detailed observations of Io during Galileo's mission. Despite the problem, Galileo did successfully fly just 102 km from Io's surface, putting the spacecraft on a trajectory that will cause it to fly into Jupiter's atmosphere in September 2003, ending the mission. One more flyby, of tiny inner moon Amalthea, is planned for November, but no images will be taken during that flyby.