SLIM, the Japan Aerospace Exploration Agency (JAXA)'s spacecraft equipped with thin-film compound solar cells developed and manufactured by Sharp Corporation, successfully made a pinpoint landing (within 100 meters of target) on the Moon's surface early on January 20, 2024. It has been confirmed that the solar cells continued to operate normally following the landing.

Sharp began developing solar cells for outer space applications in 1967, and the first solar cells were installed on the Ume satellite in 1976. Since then, we have been developing and manufacturing outer space solar cells for nearly half a century as Japan's sole solar cell manufacturer certified by JAXA, and our solar cells have been installed on about 190 satellites*2 to date.

The thin-film compound solar cells installed on SLIM were developed using the same technology as the triple-junction compound solar module*3 that achieved the world's highest*4 conversion efficiency of 32.65%*5 in 2022 with the support of NEDO*6. The structure encapsulates the solar cell within a thin film, making it lightweight and flexible enough to be mounted on curved surfaces, thus achieving specifications suitable for applications in outer space that require high efficiency and light weight.

Sharp will continue to pursue research and development of solar cells for aerospace applications and contribute to satellite and space exploration projects, including those of JAXA.

■Overview of thin-film compound solar cells on board SLIM