China's Mars orbiter captures interstellar object 3I/ATLAS

(ECNS) - China's Tianwen-1 Mars orbiter has captured images of the interstellar object 3I/ATLAS from about 30 million kilometers away, marking one of the closest observations of the object to date. The achievement could help prepare for the upcoming Tianwen-2 asteroid mission, the China National Space Administration (CNSA) said Thursday.

The relative positions of ATLAS and Tianwen-1. The image on the right is a close-up of the area shown in the left image, taken by the camera on October 3, 2025. (Photo/ China National Space Administration)

The images, taken with Tianwen-1's high-resolution camera, show the comet-like features of the object, consisting of a nucleus and surrounding coma, with a diameter of several thousand kilometers.

Scientists also compiled a short animation from a sequence of 30-second exposures showing the object's movement across space, according to the CNSA.

Discovered in July 2025 by a Chilean survey telescope, ATLAS is only the third known interstellar object to enter the solar system.

It is thought to have formed around ancient stars near the center of the Milky Way and may be older than the solar system itself, offering rare insight into the composition and evolution of exoplanetary material.

The Tianwen-1 team began preparing for the observation in early September this year. With ATLAS moving at about 58 kilometers per second and appearing 10,000 to 100,000 times dimmer than the Martian surface, the mission faced an extreme technical challenge in image targeting and stability.

Originally designed for Mars surface observation, Tianwen-1 has been orbiting the planet since February 2021.

The successful observation of ATLAS marks an extension of the probe's mission, serving as a test for China's upcoming Tianwen-2 asteroid mission.

(By Zhang Jiahao)