WORLD 🔗 Part of: The Science Horizon (23) · 19 Oct 2026 · 02:11 GMT ·2 min read

Japan Prepares World-First Sample Return Mission to Martian Moon Phobos

The Japan Aerospace Exploration Agency (JAXA) plans to launch the "Martian Moons eXploration" (MMX) mission on October 20, 2026.

NEUTRALITY 77 · BALANCED· 2 sources

The Japan Aerospace Exploration Agency (JAXA) plans to launch the "Martian Moons eXploration" (MMX) mission on October 20, 2026. The spacecraft will collect samples from Phobos. The 5-ton craft will reach the Mars region by August 2027. The spacecraft will orbit the moon for three years. JAXA intends to retrieve at least 10 grams of soil using two sampling methods. The mission includes "Idefix," a French-German rover scheduled to land on Phobos in 2029. This effort follows Japan's successful asteroid sample returns in 2010 and 2020.

Context

Space agencies have focused on Mars since the 1960s. Researchers have largely ignored the planet's moons. Scientists debate the origin of Phobos and Deimos. They investigate whether the moons formed from debris after a massive impact on Mars. They also study if gravity captured passing asteroids. The Japan Aerospace Exploration Agency (JAXA) brings experience to this challenge. This experience informs the "Martian Moons eXploration" (MMX) mission. The mission seeks to resolve questions about the formation of the Martian system.

Supportive perspectives

The mission aims to determine the origin of Phobos. Officials at the Japan Aerospace Exploration Agency (JAXA) estimate that 0.1% of the collected material is debris from Mars. This sample offers data on the past of the planet.
The MMX spacecraft carries 13 scientific instruments. The payload features a rover from France and Germany. NASA provided a sampling device for the mission. The European Space Agency (ESA) supplied a deep space communication system.
The Japan Aerospace Exploration Agency (JAXA) has proven its ability to conduct complex sample-return missions. The agency returned asteroid samples during the "Hayabusa" mission in 2010 and the "Hayabusa2" mission in 2020. These successes serve as a technical foundation for the current mission.
The spacecraft features specialized engineering to handle the environment. The exploration module features four-legged landing gear. This gear has shock absorption to mitigate the challenges of landing in Phobos's low gravity.

Critical perspectives

Space agencies have struggled to land on Phobos. Russia's 2011 mission to land on the moon failed.
The mission requires a three-year commitment at Phobos. The spacecraft will orbit the moon to collect data and samples. It begins its return journey to Earth in 2031.
Low gravity on Phobos creates engineering challenges. Spacecraft designers must account for these conditions to deploy the Idefix rover around 2029. The rover will conduct a 100-day surface survey.
The Japan Aerospace Exploration Agency (JAXA) aims to collect at least 10 grams of soil. The mission requires the precise execution of two distinct sampling methods.