JAXA's MMX mission aims to bring home a sample from a Martian moon

After a roughly yearlong cruise, MMX is expected to enter a quasi-satellite orbit around Phobos. A laser altimeter will map the moon’s shape, while an infrared spectrometer will examine minerals and search for organic compounds and water. MEGANE, an instrument developed by Johns Hopkins University Applied Physics Laboratory and Lawrence Livermore National Laboratory, will use gamma rays and neutrons to measure the surface’s elemental composition.

Sampling is the riskiest part of the plan. A coring system will try to collect about 10 grams of material during a landing, while a pneumatic sampler can use gas jets to gather loose surface grit. If the first landing succeeds, JAXA may attempt a second touchdown in a different area. Phobos’s extremely weak gravity makes both landing and sampling difficult, but surviving those steps would put MMX on course to deliver the sealed material to Earth in 2031.