Japanese Aerospace Exploration Agency (JAXA) is preparing to launch the Smart Lander for Investigating Moon (SLIM) mission to the Moon aboard an H-2A rocket on August 26. As its acronym suggests, SLIM is a small lunar lander with big ambitions. The main purpose of the lander, measuring 2.4 meters tall, 2.7 meters wide, and 1.7 meters deep, is to demonstrate accurate lunar landing techniques. These techniques will contribute to making the more challenging lunar landing areas more accessible.
Landing Site and SLIM’s Features
SLIM aims to land within 100 meters of its target destination. This is crucial, as the mission is targeting a landing within the Shioli crater. This is a young impact crater, 300 meters wide, within the Mare Nectaris, at 13 degrees south latitude and 25 degrees east longitude. The site was chosen using observational data from the Japanese orbiter SELENE (Kaguya), launched in 2007.
JAXA states that precision landings will become vital in the future. As humanity’s knowledge of the Solar System grows, access to specific and interesting sites will be necessary to advance our understanding. The mission is also a test that JAXA hopes will help accelerate space exploration using lighter systems. The SLIM architecture could make lunar and planetary landings more cost-effective. Saving weight allows for scientific payloads or sample collection.
At the time of launch, SLIM will weigh 590 kilograms. About two-thirds of the mass consists of fuel. The spacecraft is equipped with landing radar for its descent to the lunar surface. It will also use image-based navigation and obstacle detection. The landing impact will be absorbed using a crushable aluminum foam base.
Activities on the Moon
Once on the Moon, it will employ a multi-band camera to assess the local mineralogical environment. It will pay particular attention to olivine, which may have originated in the lunar mantle. Lunar lander SLIM also carries a small array of laser retroreflectors. Joining the lunar journey is the imaging and X-ray spectroscopy mission, XRISM, a collaborative effort between JAXA, NASA, and the European Space Agency (ESA). SLIM will be JAXA’s first attempt at a lunar landing. A Japanese private lunar lander, Hakuto-R, reached lunar orbit earlier this year but crashed during its landing attempt.