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Headshot of Emily Lakdawalla

Due to ion engine failure, PROCYON will not fly by an asteroid

Posted by Emily Lakdawalla

08-05-2015 16:23 CDT

Topics: Hayabusa2, mission status

It's been less than a month since the PROCYON mission announced their plans to fly by asteroid 2000 DP107, but sadly, the flyby is not going to happen. The ion engines ceased working in mid-March; my last update talked about their plans for troubleshooting. Today, reports in Japanese media indicate that these efforts were not successful, so they will not be able to change their course to fly past 2000 DP107. They think that a tiny metal fragment wandered into the space between the two electrical grids used for accelerating the ionized fuel, preventing the engine from working properly. The same report does say that the spacecraft is still functioning, and they'll continue to use it to test out its miniaturized equipment in operation in deep space.

It was a super-mini deep-space mission, so it's not surprising that it ran into challenges, but it's still sad to have lost the opportunity for an asteroid flyby. Better luck next time!

Thanks to Junya Terazono for the news tip and to Paolo for the link to the news story.

PROCYON spacecraft


PROCYON spacecraft
PROCYON (PRoximate Object Close flYby with Optical Navigation) is a 50 kg-class microsatellite developed by the University of Tokyo (UT) and JAXA/ISAS (Japan Aerospace Exploration Agency/Institute of Space and Astronautical Science). Launched with Hayabusa2, its goal is to perform a close flyby of an asteroid in early 2016.
See other posts from May 2015


Or read more blog entries about: Hayabusa2, mission status


Starmaster: 05/11/2015 11:05 CDT

This is not a failure, it is a triumph. While the original mission objective will not be achieved, the spacecraft is still functioning! Now the challenge will be to use the craft in new ways, to learn as much as is possible with what remains, to make lemonade from lemons. That this spacecraft has made it this far, and that it functions at all is a testament to human spirit, and our desire to explore. Ad Astra! Jerry Hilburn

Jeff: 05/15/2015 06:19 CDT

Well, one could wonder that given enough time, would PROCYON happen to pass another possible target close to it's current orbit? It's got an Earth flyby coming up and it's small (ie, very small) chemical thrusters are still functional, so conceivably it might be able to be redirected to another target all together!

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