Tianwen-2 probe to explore two target asteroids of high scientific research value: scientist

The Tianwen-2 probe is preparing to explore two target asteroids, near-Earth asteroid 2016HO3 and main-belt comet 311P, which are of high scientific research value and accessibility, according to Chinese scientists.

China launched its first asteroid sample-return mission, Tianwen-2, on May 29, an endeavor to shed light on the formation and evolution of asteroids and the early solar system.

The mission aims to achieve multiple goals over a decade-long expedition: collecting samples from 2016HO3 and exploring 311P, which is farther from Earth than Mars.

Known as a quasi-satellite of Earth, asteroid 2016HO3 orbits the Sun and appears to circle around Earth as well, remaining a constant companion to our planet.

Dubbed as "cosmic fossils," asteroids preserve critical information about the solar system's infancy, scientists say.

"[This asteroid] is very likely to hold the original information of the solar system at its birth, which is of great scientific research value for our understanding of the material composition of the early solar system, including its formation process and evolutionary history," said Han Siyuan, deputy director of the Lunar Exploration and Space Engineering Center.

The asteroid 2016HO3 also has a relatively stable orbit, requiring lower energy consumption for spacecraft to reach it, while enabling a viable scenario for subsequent exploration of the main-belt comet 311P, according to Han.

The second target, 311P, a celestial anomaly discovered in the main asteroid belt between Mars and Jupiter, occasionally spews out materials and resembles a comet with tails.

Its discovery challenges astronomers' conventional understanding about a comet, as the region is too close to the Sun for a comet to retain its volatile materials like water ice.

As scientists are still uncertain whether main-belt comets originated in the asteroid belt or from the edge of the solar system, these special small celestial bodies hold significant scientific research value.

The entire mission process for Tianwen-2 is complex. After launch, it will journey for about one year to reach its first target, during which it will perform deep-space maneuvers and mid-course corrections until it is about 30,000 km away from 2016HO3.

The probe will gradually approach the target, carrying out close exploration by circling and hovering over the asteroid to determine the sampling area, with a strategy of flying and probing simultaneously.

After completing the sampling, the spacecraft will fly back to the vicinity of Earth. A return capsule will separate from the main probe and is expected to deliver the samples to Earth by the end of 2027.

The main probe will then continue its voyage to rendezvous with the more distant target, the main-belt comet 311P, to carry out subsequent exploration tasks.

Asteroid 2016HO3 is located between 18 million km and 46 million km from Earth, while the main-belt comet 311P lies approximately 150 million km to 500 million km away.

Tianwen-2 probe to explore two target asteroids of high scientific research value: scientist

Chinese scientists announced Monday that they have achieved a breakthrough in yak cloning, with 10 cloned calves all naturally delivered in southwest China's Xizang Autonomous Region.

These calves, consisting of three black yaks and seven white ones, were born from March 25 to April 5 at a yak breeding and research base in Xizang's Damxung County, all meeting expected standards and steadily gaining weight.

The mass births came after the first cloned yak was born in July 2025, which has grown healthily and weighs about 183 kg now.

The achievement was made using a domestically developed breeding system that combines whole-genome selection with somatic cell cloning, following three years of research by a Chinese scientific team.

"Whole-genome selection can accurately pinpoint excellent genetic loci associated with large body size, fast growth, strong fecundity and disease resistance, high feed conversion efficiency, and tolerance to high-altitude and low-oxygen conditions (cold resistance). On this basis, somatic cell cloning enables 1:1 precise replication of the genotype through asexual rapid propagation (cloning), thereby compressing the breeding cycle to within five years," said Fang Shengguo, a professor at the College of Life Sciences at Zhejiang University and director of the State Conservation Center for Gene Resources of Endangered Wildlife.

Yak farming is one of the key industries targeted for development in Xizang during the country's 15th Five-Year Plan period (2026-2030). Traditional yak breeding has relied on phenotype selection, a process that can take up to 20 years and often leads to declining genetic quality.

Researchers said the new method can shorten the breeding cycle to less than five years by accurately identifying desirable genetic traits such as faster growth, disease resistance, feed efficiency and adaptation to high-altitude, low-oxygen environments, while enabling rapid replication of elite breeding stock.

Experts added that the technology could also support conservation efforts for rare yak genetic resources, including the endangered golden wild yak, whose population in Xizang is estimated at more than 300.

So far, the research team has developed more than 200 cloned embryos of golden wild yaks and hybrid wild-blood yaks, laying the groundwork for future embryo transfer and species recovery programs.

China achieves large-scale births of cloned yaks