China‘s space agency may become the first to bring Martian samples to Earth, with a mission targeting a return of rocks and sediment by 2031.
In the November issue of National Science Review, researchers from the Deep Space Exploration Laboratory and other Chinese institutions outlined the Tianwen-3 mission—a dual-spacecraft Mars lander project under the China National Space Administration (CNSA). During a space exploration conference in September, Jizhong Liu, Tianwen-3’s chief designer, confirmed the mission remains on schedule for a 2028 launch.
As reported by Space News, Tianwen-3 will feature a lander, an ascent vehicle, an orbiter, and a return module. The mission might also employ a helicopter and a six-legged robot to collect samples from locations beyond the immediate vicinity of the lander.
The National Science Review article, co-authored by Zengqian Hou of the Deep Space Exploration Laboratory and the Chinese Academy of Geological Sciences, revealed that 86 potential landing sites are under consideration. Most are situated in Chryse Planitia—a smooth plain near Mars’ northern equator—and Utopia Planitia, the planet’s largest impact basin, where China successfully landed a rover in 2021.
According to Hou and his colleagues, these sites are particularly promising for the primary goal of the Tianwen-3 mission: searching for evidence of past life on Mars. The locations were selected for their relatively smooth and safe landing terrain, as well as the potential for rocks and sediment to harbor preserved traces of ancient Martian life.
If launched in 2028, Tianwen-3 would return to Earth by 2031. (A one-way journey between Earth and Mars takes approximately seven to 11 months, depending on the planets’ alignment at the time.) Once the samples are retrieved, they would undergo a variety of analyses, Hou and his team explained. These would include mass spectrometry to determine their elemental composition and isotopic analysis to examine the ratios of different element variants, which could reveal signs of past life.
If Tianwen-3 stays on schedule, it could outpace NASA and the European Space Agency (ESA) by almost a decade in returning Martian samples to Earth. In April, NASA announced delays to its Mars Sample Return (MSR) mission, a collaboration with ESA, pushing key milestones into the 2030s. Under the revised timeline, the MSR lander is expected to launch in 2035, with the sample-return mission not projected until 2040.
China’s Chang’e-6 mission recently achieved a historic milestone by returning the first-ever samples from the far side of the Moon. Initial analysis of these samples uncovered evidence of volcanic activity on the lunar far side, indicating that eruptions occurred there as recently as 2.8 billion years ago.
