Chinese Probe Tianwen-2 Reaches Near-Earth Asteroid Kamoʻoalewa but Finds It Smaller Than Expected

• July 8, 2026

China’s interplanetary mission Tianwen-2 has arrived at its first target, the near-Earth asteroid 2016 HO3, also named Kamoʻoalewa, initiating scientific study of the object. This milestone marks a significant step in China’s expanding space exploration efforts.

Unexpectedly Small Asteroid Challenges Mission Team

Prior to arrival, the size of Kamoʻoalewa was estimated to be between 40 and 100 meters in diameter. However, once close to the asteroid, mission scientists and engineers realized the object is considerably smaller than initially anticipated. This discovery presents new challenges for sample collection and scientific operations planned for the mission.

Tianwen-2’s close approach to Kamoʻoalewa offers an opportunity to analyze a near-Earth object in unprecedented detail. The mission aims to gather valuable data that can inform understanding of asteroid composition and behavior, and ultimately contribute to planetary defense strategies.

The smaller-than-expected size of Kamoʻoalewa may require adjustments in the spacecraft’s approach and sampling techniques. Despite this setback, researchers remain focused on carrying out the mission’s objectives and maximizing the scientific return from the investigation of this asteroid.

Tianwen-2 represents one of the latest advancements in China’s ambitious interplanetary exploration program. The spacecraft’s study of Kamoʻoalewa will provide insight into the characteristics of small near-Earth asteroids, which are of growing interest due to their potential impact risk and resource possibilities.

Further updates on Tianwen-2’s progress and findings are awaited as the mission continues its detailed survey and sample collection efforts on this intriguing celestial body.

China’s Tianwen-2 spacecraft arrived at near-Earth asteroid Kamoʻoalewa, discovering it is significantly smaller than initial estimates suggested.