China's Tianwen-2 probe reaches asteroid Kamoʻoalewa (2016 HO3), begins exploration

China's Tianwen-2 probe has successfully reached asteroid 2016 HO3, marking a significant milestone in its first asteroid sample-return mission. Launched on May 29, 2025, the probe traveled approximately 1 billion kilometers over 400 days to arrive at a distance of 20 kilometers from the asteroid.¹²³⁴

The China National Space Administration (CNSA) announced that the probe began its scientific exploration after achieving its first detection of the asteroid on June 6, 2026. Following this, it entered a coplanar trajectory with the asteroid on June 7 and approached within 2,000 kilometers by June 19.

During the approach phase, the Tianwen-2 probe captured imagery of the asteroid, which helped refine its ephemeris, reducing positional uncertainty from hundreds of kilometers to the kilometer scale. The mission aims to collect samples from 2016 HO3 and explore the main-belt comet 311P, which is more distant than Mars.

The CNSA stated that the probe will conduct detailed scientific exploration to gather data on the asteroid's morphology, material composition, and internal structure, laying the groundwork for future sample collection operations.

This mission represents a significant step in China's space exploration efforts, showcasing advancements in technology and international collaboration in the field of planetary science.