SLIM Lander Powers Down for Long Lunar Night; JAXA Releases New Batch of Moon Snapshots

The Yomiuri Shimbun

17:25 JST, February 2, 2024

The Smart Lander for Investigating Moon, or SLIM, stopped its activities on the lunar surface and entered a dormant state around 9 a.m. on Wednesday, the Japan Aerospace Exploration Agency said Thursday. The lander’s solar panel cannot generate power now that night has fallen on the moon.

Along with the announcement, JAXA released new images of the lunar surface taken by SLIM just before the sun set.

A lunar night lasts about two Earth weeks. During the night, temperatures drop to around minus 170 C, while during the day, temperatures reach over 110 C. JAXA plans to turn the lander back on after mid-February when the lunar night ends, but it may not be possible to reactivate SLIM as the lander’s electronics could break in the harsh environment, such as from the temperature differences of over 200 degrees, according to JAXA.

The lunar craft landed the wrong way up in the early hours of Jan. 20, leaving its solar panel unable to take in sunlight. However, by Sunday night the angle with the sun had changed enough to allow the solar panel to generate power. The lander then used a special camera to successfully observe 13 locations on the moon’s surface, including a rock named after a dog breed. In the future, SLIM will analyze the composition of rocks and other materials, with the aim of achieving scientific insight into the moon’s origins.

“Seeing everyone pool their knowledge and work out measures, it was just like watching a movie,” said Kazuto Saiki, who developed SLIM’s camera and is the director of the Earth & Space Exploration Center at Ritsumeikan University. “We were able to make observations that are even better than what we expected,” he said.