China’s Tianwen-3 Mars Sample Return Mission Progressing Towards 2030 Launch
China is making significant progress in its ambitious Tianwen-3 Mars sample return mission, which is set to launch around 2030. The mission, led by the China Academy of Space Technology (CAST), aims to collect samples from Mars and bring them back to Earth for analysis. Sun Zezhou, the chief designer of China’s successful Tianwen-1 Mars orbiter and rover mission, revealed that the project is progressing “relatively smoothly.”
While NASA is currently facing budget and schedule concerns for its Mars Sample Return (MSR) mission, China’s approach to the Tianwen-3 mission is simpler yet still complex. The mission will involve two Long March 5 launches, with one carrying a lander and ascent vehicle, and the other carrying an orbiter and return module. The entry, descent, and landing process will build on the technology used in the Tianwen-1 rover landing.
The lander will be equipped with a robotic arm and a drill to collect surface samples and material from up to two meters below the surface. Additionally, there are plans to include either a six-legged crawling robot or a helicopter similar to Ingenuity to collect a more diverse set of samples. The mission aims to deliver approximately 500 grams of Martian samples back to Earth.
Sun highlighted the main challenges of the mission, including obtaining rock samples, taking off from the Martian surface, rendezvous and docking in orbit, and transferring the samples to a reentry module. These tasks require a high degree of autonomy in system design. However, China already has experience in Mars entry, descent, and landing from the Tianwen-1 mission, as well as sampling and launch capabilities from the Chang’e-5 lunar sample return mission.
The samples collected during the Tianwen-3 mission could potentially provide answers about the existence of past life on Mars. Sun’s comments were made during China’s annual parliamentary sessions in Beijing, shedding limited light on the mission’s progress. Previously, Chinese officials had announced a launch date of 2028, with samples expected to be returned in 2031. However, the recent statement suggests a delay of 26 months to the next Mars launch window.
In addition to the mission update, a recent research article published in the journal JGR Planets revealed three preselected landing zones for Tianwen-3. These areas include Amazonis Planitia, Utopia Planitia (where the Zhurong Tianwen-1 rover landed), and Chryse Planitia. The paper advises avoiding regions with frequent atmospheric eddy occurrences for the safety of the landing and ascent stages, making Chryse Planitia the optimal landing area.
Chryse Planitia is a lowland plain located at the eastern end of Valles Marineris, a vast outflow channel system. It is of astrobiological interest due to potential evidence of past flowing water on Mars. The Viking 1 lander also landed within Chryse Planitia. The chosen landing site will need to meet various criteria, including being at least 2,000 meters below the average global Martian elevation to provide sufficient atmosphere for a controlled descent.
The selection process will also consider scientific objectives, prioritizing areas with Martian terrain older than 3.5 billion years and environments suitable for the emergence and preservation of life. Returning samples from Mars is considered a top priority by Planetary Science Decadal Surveys, as it could provide unique insights into the planet’s geological processes and history.
A successful Tianwen-3 mission would be a major engineering feat and could yield groundbreaking scientific results. It has the potential to deliver biosignatures or chemical traces of past or even current life on Mars. With NASA’s MSR mission facing uncertainties, China could become the first country to secure Martian samples and perform groundbreaking analysis. The progress made by China in the Tianwen-3 mission highlights its growing capabilities in space exploration and its commitment to advancing our understanding of the Red Planet.