China’s Tianwen-2 asteroid probe has successfully rendezvoused with Kamo’oalewa, a quasi-moon of Earth, and sent back the first close-up images of the enigmatic asteroid that some scientists believe may be a fragment of the Moon.
The spacecraft, launched in May 2025 aboard a Long March 3B rocket, reached Kamo’oalewa on June 7, 2026. While the China National Space Administration has not yet officially confirmed the maneuver, independent verification from AMSAT-DL using telescopes in Germany and the Netherlands detected the orbital insertion. The probe is currently about 2,000 kilometers (1,240 miles) from the asteroid and will spend the next several weeks gradually approaching to within about 20 kilometers (12 miles).
Kamo’oalewa (designated 469219) is one of only seven known quasi-moons of Earth, objects that orbit the Sun in a path that keeps them perpetually near Earth without being gravitationally bound to it. The asteroid is between 40 and 100 meters (130 to 330 feet) across and completes one rotation every 28 minutes, faster than the typical spin barrier for asteroids, suggesting it is a solid, monolithic body rather than a loose rubble pile.
What makes the science community particularly interested is the asteroid’s reflectance spectrum. Observations from the Large Binocular Telescope in Arizona, published in 2021, found that Kamo’oalewa’s spectrum closely matches lunar silicate minerals, leading to the hypothesis that it may be a fragment ejected from the Moon by an ancient impact, possibly the one that created the Giordano Bruno crater on the lunar far side approximately 10 million years ago. Alternatively, it could be a migrated main-belt asteroid. The samples Tianwen-2 brings back should settle the question definitively.
Sampling and timeline
The mission will map Kamo’oalewa’s surface using LiDAR, cameras, and sounding radar until April 2027. Sampling will involve a challenging hover approach: the spacecraft must match the asteroid’s rapid rotation, then descend and use a robotic arm to collect material. Engineers have designed redundant sampling methods, including anchoring to the surface, to maximize the chance of success.
Departure is planned for April 24, 2027, China’s National Space Day. The sample return capsule is expected to re-enter Earth’s atmosphere approximately 1.5 years later, traveling at second cosmic velocity (around 12 kilometers per second, or 7.5 miles per second), a demanding re-entry profile that China has not previously attempted with returned samples.
After releasing the sample capsule, the Tianwen-2 spacecraft will continue onward to main-belt comet 311P/PANSTARRS, arriving around 2035 after an eight-year deep-space cruise that will also serve as a demonstration of China’s long-duration deep-space capabilities.
Tianwen-2 is the first of three planned Chinese missions that build on each other’s engineering advances. Tianwen-3, targeted for approximately 2028, aims to return samples from Mars, while Tianwen-4 will target the Jupiter system around 2030.
Sources: China’s Tianwen-2 Space Probe Has Rendezvoused With Earth’s Quasi-Moon (Wired, July 11, 2026); China’s Tianwen-2 mission has (probably) arrived at a quasi-moon of Earth (The Planetary Society, June 24, 2026)