Japan to launch spacecraft on a mission to get samples from a Martian moon

TOKYO (AP) — Japan is set to launch a spacecraft on the world's first mission to bring back samples from Phobos, one of the two small, potato-shaped moons orbiting Mars. Scientists hope the mission, which is expected to take five years, will provide clues to how Phobos and its smaller sibling Deimos formed, and hopefully even shed light on the origins of life in the solar system. The Japan Aerospace Exploration Agency’s launch of the spacecraft Tuesday on a new Japanese mainstay H-3 rocket comes as the United States, China and others consider sending astronauts to Mars.

Samples from Phobos will provide useful data for scientists to consider using a Martian moon as a base for a future manned mission to the planet, said MMX project manager Yasuhiro Kawakatsu. “Despite their potential importance, Martian moons have never been fully investigated,” Kawakatsu said. “They are known as the most important unclimbed mountains in the solar system.” Japan leads the international mission that includes equipment and communications support from NASA and other national space agencies.

JAXA aims to study how Mars’ moons formed Since the 1960s, dozens of missions have been sent to Mars, but its moons largely remain a mystery. Phobos and Deimos take their names from the Greek mythological personifications of fear and terror, sons of the war god Ares, whose Roman counterpart is Mars. Multiple Russian attempts to land on Phobos, including one in 2011, have failed.

A key question will be how they formed and what they are made of. Some scientists think the two irregular crater-pocked bodies could be remnants of debris formed after a large celestial object crashed into Mars. Others say the moons could be asteroids that have come from elsewhere.

JAXA officials think samples from Phobos will provide answers. “We can almost certainly come to a conclusion by analyzing (Phobos) soil samples,” MMX principal investigator Kiyoshi Kuramoto said. Scientists chose to collect samples from Phobos mainly because the moon is closer to Mars than Deimos and therefore may have more information about the planet.

Material from Mars is expected to make up about 0.1% of the material collected from Phobos, JAXA officials say. Phobos, about 20 to 30 kilometers (10 to 20 miles) in diameter, orbits Mars at a distance of about 6,000 kilometers (3,700 miles) three times a day.