China's Chang'e-6 mission uncovers rare water‑rich CI chondrite fragments in lunar samples

China's Chang'e‑6 spacecraft returned rock and dust from the lunar far side’s South Pole‑Aitken basin, landing in Inner Mongolia on 25 June 2024. A research team led by Jintuan Wang examined more than 5,000 microscopic particles and identified seven tiny clasts whose chemistry matches CI carbonaceous chondrites – a class of rare, water‑rich meteorites never before confirmed on the Moon.

The findings, published in the 2025 Proceedings of the National Academy of Sciences, suggest that such fragile, hydrated bodies impacted the Earth‑Moon system far more frequently than the terrestrial meteorite record indicates. Because CI chondrites retain a chemical signature close to the early solar system, the discovery provides new insight into the composition of ancient impactors and the history of material exchange between asteroids and the lunar surface.

The study underscores the scientific value of Chang'e‑6’s far‑side sampling and opens the possibility that additional exotic extraterrestrial materials may be preserved in lunar regolith.