Software update causes $286 million Japanese satellite to break apart in orbit

You’ve probably experienced a bad software update before. Maybe it slowed down your old iPhone. Maybe it reduced your laptop’s battery life. It probably didn’t destroy your $286 million satellite.
That is, unfortunately, exactly what happened to Japan’s space agency JAXA recently. In February of this year they launched a 2.4 ton, 14-meter orbital x-ray telescope called Hitomi. It was expected to remain in orbit for at least three years, but now, just three months later, it has become the subject of a post-mortem investigation after JAXA accidentally turned it into space rubble with a
glitchy update.
After delivering the new software, JAXA attempted to position the satellite to observe galaxy Markarian 205. The faulty software caused Hitomi to develop an attitude problem — as in its attitude control system erroneously reported that the satellite had started to rotate.

The very system that was designed to correct for unanticipated spin actually made matters worse when it kicked in. The longer Hitomi’s systems thought they were dealing with spin in one direction, the longer the ACS worked in the opposite direction to compensate.
That made Hitomi spin faster and faster, until ultimately “object separation” took place. Solar panels and other parts that were “vulnerable to the rotation” broke loose from the satellite. When it was all over, Hitomi was dead in space, floating in six to ten pieces.
From start to finish, it took around seven hours for the $286 million Hitomi to go from telescope to space trash. Bad timing was a contributing factor here, too. JAXA’s timeline shows that communications with Hitomi were blacked out at a critical moment as it passed the South Atlantic Anomaly. Their crew on the ground never had a chance to intervene before Hitomi met its catastrophic end.