Tokyo, Japan – In a historic moment for Japan’s space program, the country’s Moon lander, Slim, landed on the lunar surface but ended up on its nose. The first image of the spacecraft shows it in a rotated position, causing difficulties in generating the necessary electricity to function. The small robot, Sora-Q, which was ejected from Slim just before touchdown, captured the image. Officials from the Japanese space agency, Jaxa, explained that an abnormality in the main engine affected the landing attitude, leading to the unintended position.
The problem seems to stem from one of the thrusters on Slim malfunctioning during the descent. To transmit the image back to Earth, Sora-Q had to send it to another ejected robot, Lunar Excursion Vehicle 1 (Lev-1), which has independent communication with mission control. The lander itself had to be shut down three hours after arrival because its solar cells couldn’t operate effectively. Jaxa officials believe that Slim’s orientation prevents the solar cells from receiving sunlight. However, they hope to reactivate Slim when the lighting angles shift at the landing location.
Before hibernation, controllers were able to retrieve images of the lunar surface taken by Slim’s onboard infrared camera. These images reveal the craft on a slope surrounded by small rocks at the edge of the Shioli crater. The successful landing makes Jaxa the fifth national space agency to achieve a soft touchdown on the Moon, joining the ranks of the US, the former Soviet Union, China, and India. Statistically, landing softly on the lunar surface has proven to be a challenge, with only about half of all attempts succeeding.
Jaxa implemented new precision-navigation technologies for the mission, using rapid image processing and crater mapping to avoid hazards and reach the desired landing site. Engineers aimed to land within 100 meters of their target, and they accomplished this goal. Slim ended up approximately 55 meters east of the original landing site due to a decision made by the onboard computer during descent to avoid obstacles.
Despite the challenges faced by Slim, two rovers deployed alongside it, Sora-Q and Lev-1, achieved successful movement and operations on the lunar surface. Jaxa considers the inter-robot communication and autonomous operations of Lev-1’s leaping movements as groundbreaking achievements. The valuable knowledge and experience gained will contribute to future lunar explorations, as the acquired technology will be applied to upcoming missions.
Japan’s Moon lander, Slim, may have encountered setbacks, but Jaxa remains optimistic about the mission’s potential and the valuable lessons learned for future space exploration.