Japan's Mars Moon Mission Launches 19 October. The Prize Is 10 Grams of Phobos
Key takeaways
- MMX launches on an H3 from Tanegashima at 19:41 UTC on 19 October
- The launch window runs to 7 November
- It aims to return about 10 grams of Phobos to Earth, with samples leaving Mars orbit in 2030
- The 25 kg Idefix rover is a French-German contribution
On 19 October, an H3 rocket is due to lift off from Tanegashima carrying one of the more audacious missions of the decade. Japan's Martian Moons eXploration spacecraft, MMX, is heading for Mars to land on its moon Phobos, scoop up around 10 grams of it, and bring it home.
The launch details
Liftoff is scheduled for 19:41 UTC on 19 October (3:41pm EDT, and 4:41am JST on 20 October). That is the first day of a launch window that runs to 7 November. The trip to Mars takes about a year.
What MMX is actually doing
Ten grams does not sound like much. It is about the weight of a few coins. But Phobos is a fascinating target, and nobody has ever returned a sample from a Martian moon. Scientists still argue about whether Phobos is a captured asteroid or a chunk of Mars thrown into orbit by a giant impact. A sample could settle that, and it could also tell us about the early history of the inner solar system.
MMX will leave Mars orbit with its sample in 2030 and deliver it to Earth about a year later.
The rover riding along
MMX carries Idefix, a 25 kilogram rover built by Germany's DLR and France's CNES. It will be dropped onto Phobos to study the surface up close, which also helps with the risky business of choosing where to collect the sample. Yes, it is named after the dog in Asterix.
Why this one matters
Japan has form here. JAXA has already returned samples from two asteroids, Itokawa in 2010 and Ryugu in 2020. MMX is a step up in difficulty, with Mars gravity to deal with and a moon that has almost none.
If you want to follow along, the window gives JAXA a few weeks of slack, so a delay of a day or two for weather would not be unusual. Check JAXA's channels on the day, and remember the time difference if you are watching from Europe or the Americas: it is the early hours of 20 October in Japan.
