All is not lost JAXA

Junked? Maybe not. Hitomi, a Japanese astronomy satellite, was thought to be lost after it failed to come online. Now the Japanese Aerospace Exploration Agency says the satellite has phoned home – but a full recovery will take months.

Hitomi launched on 17 February and was due to come online on 26 March, but failed to communicate with Earth. A tweet by the US Joint Space Operations Center reported five pieces of debris around the satellite shortly afterwards.

But all may not be lost. The Japan Aerospace Exploration Agency (JAXA) heard a brief signal burst from the craft on 28 March, and video taken from the ground suggested it was tumbling through space.


“That indicates the sat was at that point alive, just unable to point its antenna at Earth,” says Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics. He says it might be possible to talk to Hitomi and stop it tumbling.

In an update on 29 March, JAXA’s Masaki Fujimoto reported they could still hear beacon signals from Hitomi, and that the spacecraft is probably still intact. The debris was probably just a few pieces that flaked off, but nothing essential. The source of the problem was a loss of directional control, which risked depleting the sat’s batteries.

“Wonderful news!!” tweeted Emily Lakdawalla of the Planetary Society. “A communicating spacecraft is a spacecraft that maybe can be saved!”

While there is hope for recovery, JAXA says, it won’t be easy.

Hitomi’s mission is to observe the universe in X-rays, investigating matters such as the birth of black holes and the origins of cosmic rays. Before losing contact, the satellite was returning the highest resolution X-ray spectra ever, McDowell says.

“If you told me we were never going to hear from the sat again, I would be devastated but not surprised,” he says. “It’ll be a big loss if they don’t get it back.”