Concept of the solar ring mission: An overview

The concept of the Solar Ring mission was gradually formed from L5/L4 mission concept, and the proposal of its pre-phasestudy was funded by the National Natural Science Foundation of China in November 2018 and then by theStrategic Priority Program of Chinese Academy of Sciences in space sciences in May 2019. Solar Ring mission will be thefirst attempt to routinely monitor and study the Sun and inner heliosphere from a full $360$-degreeperspective in the ecliptic plane. The current preliminary design of the Solar Ring mission is to deploy six spacecraft, grouped in threepairs, on a sub-AU orbit around the Sun. The two spacecraft in each groupare separated by about $30^\circ$ and every two groups by about $120^\circ$. This configuration with necessaryscience payloads will allow us toestablish three unprecedented capabilities: (1) determine the photospheric vector magneticfield with unambiguity, (2) provide $360$-degree maps of the Sun and the inner heliosphere routinely, and (3) resolve the solar wind structuresat multiple scales and multiple longitudes. With these capabilities, the Solar Ring mission aims to addressthe origin of solar cycle, the origin of solar eruptions, the origin ofsolar wind structures and the origin of severe space weather events. The successful accomplishment of the missionwill advance our understanding of the star and the space environment that hold our life and enhance our capability ofexpanding the next new territory of human.