What "Kaguya" Has Seen in Her Hometown

Abstract

The Kaguya mission was the large scaled exploration program for the Moon since the Apollo mission. Aimed to reveal its origin and evolution process and also to help planning the future utilization of the Moon, the Kaguya satellite carried 14 scientific instruments to the lunar orbit and successfully observed the elemental and mineral composition, topography, underground structure, magnetic anomaly, and gravity field over the entire surface of the Moon. One of the instruments, Gamma-Ray Spectrometer with high energy resolution, has measured global distributions of the major and trace elements on the Moon. A material composition that constitutes a stellar object can be determined by observing line gamma rays emitted from its surface, providing an important clue for its history. With an emphasis on the gamma-ray observation, we introduce the results on the exploration of the lunar materials achieved by the Kaguya mission and the future direction of the lunar exploration.