Japan has become the fifth country to successfully land a spacecraft on the moon, after its SLIM mission touched down on the lunar surface on Friday.
The Smart Lander for Investigating Moon (SLIM) was launched in September 2023 and reached the moon on October 4. After orbiting the moon for more than three months, it began its descent on January 19 at 10:00 a.m. ET and landed at 10:20 a.m. ET, according to the Japan Aerospace Exploration Agency (JAXA).
SLIM is a small-scale robotic explorer that carries new precision technology to demonstrate a “pinpoint” landing. Unlike previous lunar missions that targeted landing zones that spanned many kilometers, SLIM aimed to land within 100 meters of a specific point.
The landing site was near the small Shioli crater within a lunar plain called the Sea of Nectar, which lies just south of the Sea of Tranquility, where Apollo 11 landed in 1969. The crater is surrounded by rocky debris that could reveal insights into the moon’s origin and evolution.
SLIM used an image-matching-based navigation system to autonomously adjust its trajectory as it approached the lunar surface. It also had five crushable, 3D-printed aluminum lattice landing legs to absorb the impact of touchdown.
Along with SLIM, JAXA also sent a small rover called Lunar Excursion Vehicle 1 (LEV-1), which was ejected from the lander at an altitude of two meters. LEV-1 is designed to hop around the moon using a spring mechanism and collect images and data.
JAXA confirmed the success of the landing during a press conference on Friday, but said it will take up to a month to verify the accuracy of the pinpoint landing. The agency also said that the solar panels on SLIM were not generating electricity as expected, which could limit the operation time of the lander.
Japan’s SLIM mission is a milestone for the country’s space program, as well as for the global exploration of the moon. It joins the exclusive club of the United States, the former Soviet Union, China and India, which have achieved robotic lunar landings in the past.
The mission also showcases Japan’s technological innovation and ambition, as it plans to send more spacecraft and eventually humans to the moon in the future.