Analysis of lunar regolith returned by Chang’e-6 has revealed definitive evidence of impact-delivered material from a CI chondrite-like asteroid. This discovery provides a direct physical record of a specific type of extraterrestrial body colliding with the Moon.

Researchers identified rare mineral fragments and distinct chemical signatures within the samples that are alien to the lunar environment. These include particles with exceptionally high magnesium-to-iron ratios and unique sulfide compositions inconsistent with known lunar or common meteoritic origins. Their mineralogy and isotopic fingerprint closely match those of CI chondrites, a rare, primitive class of carbonaceous asteroids rich in water and volatile elements.

The presence of this material is significant for several reasons. First, it confirms the Moon acts as a natural archive, preserving debris from impacts across solar system history. Second, CI chondrites are fragile and water-rich, making their survival through a high-velocity impact event noteworthy. Their detection suggests some volatile components may be retained during such collisions.

This finding offers a new, tangible link to understand the composition of the impactor population that has bombarded the Earth-Moon system. It also implies that volatile elements essential for life, commonly found in carbonaceous asteroids, have been delivered to the lunar surface via such impacts, influencing the volatile inventory of airless bodies. The Chang’e-6 samples thus provide a unique window into both the lunar impact history and the nature of primitive solar system materials.

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