China's Xuntian CSST set to map the cosmos with Hubble-scale sky coverage by 2027

China is advancing the CSST/Xuntian space telescope, a bus-sized observatory with a 2-meter primary mirror and a 2.5-billion-pixel camera designed to survey the sky from near-UV to near-IR with a field of view about 300 times larger than Hubble. Slated for launch in early 2027, it will operate in low Earth orbit co‑orbiting with the Tiangong space station and can be serviced by astronauts. An end-to-end simulation study published ahead of launch highlights potential science across cosmology, galaxies, the Milky Way, and planetary systems, including insights into dark matter and dark energy.