Image: Artist’s concept of Hitomi, scoping out a black hole / JAXA

After a full month spinning out of control in space, Japan’s Space Agency has finally figured out how it lost control of Hitomi, a very expensive satellite that was hunting for black holes. This also means the agency will never get it back.


JAXA announced today that it has exhausted all efforts at getting Hitomi back and will leave the $273 million satellite—which it had previously described as key to unlocking the mysteries of the universe—to drift off into space. Although the agency will never get Hitomi back, it does, at long last, have an explanation for just what it was that caused the problems for the highly-anticipated satellite almost immediately after it was launched.

It wasn’t a collision with debris or a malfunctioning thruster, as had been speculated. Instead, the source of the trouble was a series of system errors (including software and human errors) that caused the satellite to spin wildly out of control. Even worse, the solar panels on both sides of the satellite broke away at their bases (potentially explaining some of that debris that was spotted around Hitomi immediately after it began having problems). This killed one of its primary power sources.

Hitomi had barely clocked a month in space before signs that something had gone wrong emerged. First, debris was spotted around the satellite. Then, attempts at contacting Hitomi were met with an eerie silence, until JAXA researchers spotted the satellite spinning wildly. Even then, the agency believed it might find a way to get the black hole-monitoring satellite back on track.

When the satellite re-emerged and sent some strange, terse messages back to JAXA, the researchers hoped it was a sign that the damage was relatively minor. Short and cryptic as they were, the mere fact that Hitomi had sent messages gave them hope that it could still be recovered.

Now, JAXA has not only given up hope of ever retrieving the lost satellite, but it also doubts whether it actually received any messages from the crippled Hitomi at all. Researchers inspected the messages much more closely and have noticed something odd. All the messages seemed to come from slightly different frequencies. While the agency had initially blamed damage for the nonsensical dispatches, it now looks like the real reason is that the “messages” were never from Hitomi at all. They were probably just the result of intercepted radio interference.



Now that it has given up all hope of ever retrieving the satellite, JAXA says it is going to focus on resolving the systematic issues that led to the malfunction, so that the next one doesn’t drift away from us, spinning alone into space.

[This post has been updated to correct erroneous statements that the loss of the solar panels caused the Hitomi malfunction. Rather, the panels broke off in response to that malfunction.]