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JAXA Launches MMX Mission Toward Phobos Sample Return

By Drooid · Oct 21, 2026, 2:28 AM UTC · How we work

Summary

Story summary

JAXA launched MMX on an H3 rocket from Tanegashima on 20 Oct 2026.
MMX will collect 10 grams of Phobos material and return it to Earth in 2031.
It will reach Mars orbit in August 2027 and enter a quasi-satellite orbit around Phobos.
The 25-kg rover Idefix will spend 100 days on Phobos in 2029 to scout sites.
Scientists hope the samples will show whether Phobos and Deimos are captured asteroids or impact debris.

History

Historical Context

In 2014, JAXA’s Hayabusa2 mission successfully returned 1.4 kg of asteroid Ryugu material to Earth after a two-year journey, proving sample-return feasibility. NASA’s OSIRIS-REx spacecraft collected 60 g of Bennu regolith, costing roughly $800 million, and delivered the sample to Utah after a four-year mission in September 2023. Similarly, JAXA’s 2026 MMX launch on an H3 rocket from Tanegashima aims to retrieve 10 g of Phobos material, deploying the 25-kg Idefix rover in 2029. If MMX confirms Phobos as a captured asteroid, it will reshape planetary-formation models and guide future international crewed Mars-orbit missions.

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Story summary

JAXA launched MMX on an H3 rocket from Tanegashima on 20 Oct 2026.
MMX will collect 10 grams of Phobos material and return it to Earth in 2031.
It will reach Mars orbit in August 2027 and enter a quasi-satellite orbit around Phobos.
The 25-kg rover Idefix will spend 100 days on Phobos in 2029 to scout sites.
Scientists hope the samples will show whether Phobos and Deimos are captured asteroids or impact debris.

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