Ahead of the launch: What is the Tianwen-2 mission?

China's asteroid probing mission, Tianwen-2, is set for launch on Thursday. The mission will conduct multiple deep space tasks in a single launch, including a flyby and sample-return mission to near-Earth asteroid 2016 HO3 as well as a flyby investigation of the main-belt comet 311P.

Spanning an operational period of 9.5 years, Tianwen-2 will first target asteroid 2016 HO3, often referred to as Earth's "quasi-satellite" due to its stable orbit near our planet. Scientists consider it a "living fossil" of the solar system, preserving primitive material from the early days of planetary formation. By retrieving samples from its surface, researchers hope to gain new insights into the composition and evolution of early solar system bodies.

Following the sample-return phase, the spacecraft will continue to study comet 311P, which resides in the asteroid belt between Mars and Jupiter. The object is believed to exhibit both asteroid-like and comet-like characteristics. Tianwen-2's observations are expected to fill critical gaps in current knowledge about the physical structure, composition, and evolutionary mechanisms of small solar system bodies.

Currently, all pre-launch preparations are progressing smoothly at the Xichang Satellite Launch Center in southwest China.