SOLAR-C (official name "High-sensitivity Solar Ultraviolet Spectroscopic Satellite"[1]) is a planned Sun-observing satellite being developed by the Japan Aerospace Exploration Agency (JAXA), the National Astronomical Observatory of Japan (NAOJ), and international collaborators. It will be the follow-up to the Hinode (SOLAR-B) and Yohkoh (SOLAR-A) missions and will carry the EUV High-throughput Spectroscopic Telescope (EUVST) and the Solar Spectral Irradiance Monitor (SoSpIM).[2][3][4][5][6] It is scheduled to launch in fiscal year 2028.[7]