Japan’s MMX mission targets Phobos sample return

Japan’s Martian Moons eXploration mission is scheduled to launch October 20 aboard an H3 rocket from Tanegashima, beginning a planned journey to collect material from Phobos and return it to Earth. The Japan Aerospace Exploration Agency, which leads the mission, has set the launch for 4:41 a.m. Japan Standard Time, according to its schedule. The robotic spacecraft is designed to study both of Mars’ moons, with its sample collection focused on Phobos. JAXA aims to bring back at least 10 grams of material. The return capsule is expected to land in Australia in 2031, after a mission expected to last about five years. These dates and operations remain plans; the spacecraft has not yet launched and no samples have been collected. Scientists hope the material will help answer a longstanding question about the moons’ origins. One explanation is that Phobos and Deimos formed from debris after a large object struck Mars. Another is that they are asteroids captured by the planet’s gravity. Their formation remains unresolved, and analysis of returned material could help distinguish between the possibilities. The mission is expected to reach the Mars region in August 2027. It will then...