V19

Presentation Title:	The SOLAR-C Mission: a progress report of the design and development
Author(s):	H. Hara (NAOJ) and the SOLAR-C team

Abstract:

This talk will provide a brief overview of the progress of the SOLAR-C mission. SOLAR-C is a JAXA-led mission in collaboration with multiple organizations of NASA, ASI, CNES, DLR, SSO, and ESA for launch in FY2028. Since March 2024, the SOLAR-C program has become a JAXA Project, upgraded from Phase A in the Pre-Project status and is in Phase B. The satellite carries the EUV high-throughput Spectroscopic Telescope (EUVST), which consists of an EUV imaging spectrograph and a slit-jaw imager. The high-sensitivity spectrograph with a field of view of 280 arcsec squares will observe the solar atmosphere from the chromosphere up to the corona with a seamless temperature coverage by multiple EUV bands in the wavelength range of 17–123 nm and a high spatial resolution of 0.4”. The slit-jaw imager will provide similar high-resolution photospheric/chromospheric imaging data not only for playing a role in locating the spectrograph’s slit position on the Sun for the co-alignment to the other dataset but also for monitoring and investigating the photospheric/chromospheric solar activity. An EUV spectral irradiance monitor assembled to the EUVST external surface will monitor the whole Sun in two EUVST wavelength bands to watch the solar activity influencing the Earth’s atmosphere and cross-calibrate the spectrograph throughput. The SOLAR-C spectral and imaging diagnostics will provide powerful tools to access the fundamental physical processes for achieving the primary SOLAR-C science goals. Coordinating with the MUSE to enable high-cadence spatial coverage, in addition to large-aperture ground-based observatories to include high-resolution magnetic fields, will synergistically enhance the SOLAR-C scientific outcomes.

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