China's Tianwen-2 mission, launched on May 29, 2025, marks a significant advancement in the nation's space exploration efforts. The mission aims to collect samples from the near-Earth asteroid 2016 HO3 and explore the main-belt comet 311P/PANSTARRS, providing valuable insights into the early solar system.
The Tianwen-2 spacecraft was launched aboard a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan Province. Approximately 18 minutes after liftoff, the spacecraft was successfully placed into a transfer orbit toward its target asteroid. The mission is expected to last about a decade, with the spacecraft scheduled to arrive at asteroid 2016 HO3 in July 2026. After collecting samples, the spacecraft will return to Earth, with the sample capsule expected to land in November 2027. Subsequently, the mission will continue its journey to comet 311P/PANSTARRS, with arrival anticipated in 2035.
Asteroid 2016 HO3, also known as 469219 Kamoʻoalewa, is a small celestial body that orbits the Sun in a path closely aligned with Earth's orbit. This unique trajectory classifies it as a quasi-satellite of Earth. The mission aims to collect samples from this asteroid to study its composition and gain insights into the formation and evolution of the solar system.
Comet 311P/PANSTARRS, located in the main asteroid belt between Mars and Jupiter, exhibits both asteroid-like and comet-like characteristics. The Tianwen-2 mission will conduct remote sensing observations of this comet to understand its composition and activity, contributing to the broader knowledge of small celestial bodies in the solar system.
The Tianwen-2 spacecraft is equipped with a suite of scientific instruments, including cameras, spectrometers, and a radar sounder, designed to analyze the physical properties, composition, and internal structures of its target bodies. These instruments will enable detailed studies of the asteroid and comet, enhancing our understanding of the early solar system.
This mission underscores China's growing capabilities in space exploration and its commitment to advancing scientific knowledge of the cosmos.