It has been a long trek to develop space missions to study the Sun in China. The earliest effort could be dated back to 1976, when the first solar mission proposal, named ASTRON-1, was accepted. In 1990s, some solar payloads on manned spacecraft series Shenzhou were implemented. The Space Solar Observatory (SST for short) was also proposed in 1990s. In 2000s, the SMall Explorer for Solar Eruptions (SMESE, a joint Chinese-French mission), Kuafu, and others were proposed and promoted. But none of them had gone into the engineering stage, except some solar physics related payloads on the Shenzhou-2 mission. In order to better organize the space science missions, the Chinese Academy of Sciences (CAS) opened a new domain named as Strategic Priority Research Program on Space Science in 2011. It in particular supports the development of scientific satellites at three different levels: conception study (Phase 0/A), background study (Phase A/B), and mission engineering study (Phase C/D).

    The conception study of the Advanced Space-based Solar Observatory (ASO-S) was carried out from September 2011 to March 2013. Its background study started in January 2014 and completed by the end of 2015, which is required for a mission project to be formally approved for the phase B study on the track of the Strategic Priority Research Program on Space Science. The phase B study of the ASO-S starts in middle 2017 and will last for about 20 months.