After traveling more than a billion kilometers through space, China's Tianwen-2 probe has successfully rendezvoused with the near-Earth asteroid Kamoʻoalewa — a small, fast-spinning rock that may actually be a fragment of the Moon.
On July 6, 2026, the China National Space Administration's Tianwen-2 spacecraft closed to within 20 kilometers of asteroid 469219 Kamoʻoalewa, marking the beginning of its detailed science campaign. The mission aims to collect samples from the surface of this 27-meter-diameter asteroid and return them to Earth — a feat that would make China only the third nation, after Japan and the United States, to bring back material from an asteroid.
Kamoʻoalewa orbits the Sun in a 1:1 resonance with Earth, meaning it appears to circle our planet like a distant second moon. Spectroscopic analysis suggests its composition closely matches lunar rock, leading scientists to suspect it may be a fragment blasted off the Moon's surface by an ancient impact. If the samples confirm this, Kamoʻoalewa would be the first confirmed piece of the Moon to be studied up close since the Apollo era.
Asteroid sample-return missions are among the most scientifically valuable in planetary science. The material collected from Kamoʻoalewa is pristine — never heated or altered by passage through Earth's atmosphere — and can reveal the original composition of the early solar system. If the asteroid is indeed a lunar fragment, the samples will provide a window into the Moon's ancient past that even Apollo samples cannot fully offer. The success of Tianwen-2 also demonstrates China's growing capability in deep-space exploration, following its historic Mars landing with Tianwen-1 in 2021 and the ongoing Chang'e lunar sample-return missions.
For planetary scientists, Kamoʻoalewa holds answers to questions about how Earth acquired its Moon, how near-Earth objects form, and how to defend against potentially hazardous asteroids. The samples now being collected may contain clues to all three.