SOLAR-C is under development with the target launch in FY2028.

01. Target Launch

The SOLAR-C team is working for a target launch of FY2028. This period is around the maximum phase of Solar Cycle 25, which enhances the opportunities to observe the solar active regions and the solar flares.

Fig. 1: Schedule

Even if the launch is slightly delayed, the defined science objectives will be achieved because active regions and flares continue to occur after the cycle maximum.

02. Status in Japan

In response to the call for JAXA's Competitively-chosen Medium-sized Focused Missions (September 2017), the Solar-C Working Group proposed the mission concept of SOLAR-C (January 2018), which was approved as a result of the review by the review panel under Advisory Committees for Space Science and Engineering and was reported to the ISAS Director General (July 2018). Following the report, ISAS decided to phase up this mission to Pre-Phase A1b (Idea implementation process). After it passed the international science review (December 2018) and the ISAS pre-project candidate selection review (March 2019), SOLAR-C is now under Pre-Phase A2 (Mission defining phase) since April 2019. In April 2020, SOLAR-C is downselected at ISAS for the 4th Competitively-chosen Middle-class mission. SOLAR-C passed the mission definition review (MDR) in July 2022 and project preparation review in September 2022. In November 2022, the SOLAR-C Pre-Project Team was established. It then passed the system requirements review (SRR) in December 2022, the system definition review (SDR) in December 2023, and the project transition review in February 2024, and the SOLAR-C Project Team was launched in March 2024.

03. Future Milestones

In the project phase, SOLAR-C goes through the basic design (Phase B), detailed design (Phase C), fabrication/verification (Phase D), and launch and operation (Phase E).