China's Tianwen-2 spacecraft has begun a critical series of small propulsive maneuvers following a main engine burn on June 7, positioning itself for an asteroid rendezvous in July. The maneuvers, detected by radio tracking, refine the probe's trajectory as it closes in on its target — a small near-Earth object designated 2016 HO3.
The Tianwen-2 mission launched in May 2025 atop a Long March 3B rocket from Xichang. Its primary objective is to collect samples from the asteroid's surface and return them to Earth, a feat only NASA's OSIRIS-REx and Japan's Hayabusa2 have achieved. The spacecraft is equipped with a robotic sampling arm, a drill, and a reentry capsule for the return phase.
Radio tracking data from amateur and professional observers confirm the burn sequence, which includes several small trajectory-correction burns after the major deep-space maneuver. These adjustments are essential for a precise flyby and eventual orbit insertion around the asteroid, expected in late July 2025.
This marks China's second deep-space sample return attempt after the successful Chang'e-5 lunar mission. Tianwen-2 will also serve as a testbed for technologies needed for the country's planned Mars sample return mission in the 2030s. The asteroid 2016 HO3 is approximately 40 to 100 meters in size and is a quasi-satellite of Earth.
No official updates from the China National Space Administration have been published on the burn sequence, leaving some details reliant on external tracking. The mission's success hinges on precise navigation and the complex sample collection procedure, both of which face inherent risks in deep-space operations.