Space Particle Monitor (SPM) is a compact, lightweight and low-cost radiation measurement device that applies two PIN silicon semiconductor detectors. SPM was developed in the SERVIS (Space Environment Reliability Verification Integrated System) project under the Ministry of Economy, Trade and Industry (METI), and is mounted on JAXA RAPid Innovative payload demonstration Satellite 1 (RAPIS-1) launched in January 2019. We achieved the full success that the discrimination and energy content of electrons, protons, and heavy ions could be observed. This paper reports on-orbit demonstration results of SPM
