Japan Launches MMX Mission to Mars Moon Phobos for Samples

Japan’s Martian Moons eXploration (MMX) mission launched on Tuesday, heading to Mars moon Phobos to collect samples and bring them back to Earth.

The uncrewed MMX mission lifted off from the Tanegashima Space Center at 4:41 a.m. local time (1941 GMT Monday) aboard an H3 rocket. The Japan Aerospace Exploration Agency (JAXA) announced the probe successfully separated from the H3 rocket and was beginning its journey towards the Martian system an hour after launch. JAXA received signals from the spacecraft, confirming normal operation.

The mission is expected to reach Mars in August 2027. MMX will attempt to collect samples from Phobos, the larger of Mars' two moons, and deploy the German-French rover IDEFIX to explore the surface. The mission aims to return collected material to Earth in 2031. Scientists hope the probe's discoveries will help lay the groundwork for eventual human exploration and unlock the mysterious origins of the Solar System.

NASA's Science Mission Directorate administrator Nicky Fox stated that samples from MMX will bring forth paradigm-shifting science on the Mars system, especially as NASA prepares to send humans to Mars. France and Germany are contributing a small rover, and a French-built infrared instrument will help examine the moons’ surfaces and identify suitable landing sites. The central question for scientists is the origin of Phobos and Deimos, whether they are captured asteroids or formed from debris from a massive collision involving Mars.

Phobos is an irregular body measuring about 27 kilometers at its widest point and orbits less than 6,000 kilometers above the Martian surface. Deimos, the smaller moon, circles further out at an altitude exceeding 20,000 kilometers. The MMX mission is an international endeavor led by JAXA, with support from NASA, which will supply the Mars-moon Exploration with Gamma Ray and Neutrons (MEGANE) detector.

The MEGANE detector, developed by Johns Hopkins Applied Physics Laboratory (APL) and Lawrence Livermore National Laboratory, could help answer the question of the moons' origin. The $578 million mission features a 5-ton spacecraft. Japan has previously completed two asteroid sample returns.