The Japanese SLIM (Smart Lander for Investigating Moon) module, which arrived on the surface of the moon in January, survived the harsh lunar night, the equivalent of two sunless and frozen Earth weeks, according to the BBC.
“A command was sent to SLIM last night and a response was received”the Japanese space agency Jaxa said on X.
SLIM mooned in January near the Moon's equator, where the surface temperature reaches over 100 degrees Celsius at midday, but then drops to -130 degrees Celsius during the lunar night. Communication with the lunar module was interrupted after a short time because it was lunar noon, which means that the temperature of the communication equipment was very high. Preparations have begun for the resumption of communication after the temperatures drop further. Unfortunately, however, because the ship landed in a position where its solar panels are oriented the wrong way in relation to the Sun, they were unable to generate any more energy. In these conditions, SLIM entered standby mode. The Jaxa company said at the time that SLIM (Smart Lander for Investigating Moon) was not designed for harsh lunar nights.
At one point, changing the direction of sunlight allowed it to send images back, but it stopped again when the lunar night began. Then the Japanese said it was possible to start working again in mid-February when the Sun would once again shine on Slim's solar cells. However, there were fears that SLIM would not survive the lunar night, the extremely low temperature being one of the current challenges of long-duration space missions.
SLIM module, Photo: JAXA
“The news that SLIM has restarted after the cold lunar night is significant,” said Dr. Simeon Barber from the UK's Open University. “Surviving the lunar night is one of the key technological challenges that must be overcome if we are to establish long-duration robotic or human missions to the Moon,” he also said.
During its short previous wake period, SLIM was able to study the environment in detail and transmit new images to Earth. JAXA hopes that after surviving the lunar night, it will be able to continue its work.
The January landing made JAXA the fifth space agency to achieve a light landing, following the US, the former Soviet Union, China and India.
A U.S. spacecraft, the Odysseus landing module, made history Thursday by becoming the first privately built and operated robot to perform a smooth landing on the Moon. Like SLIM, this module also touched the surface of the Moon in an odd position. Controllers from the operating company, Intuitive Machines, believe their robot tipped to one side when it hit the ground. However, Odysseus appears to still be functional and communicating with Earth.
No images from the surface mission have been released yet.