Tianwen-3

What is Tianwen-3?

Tianwen-3 is China’s planned Mars sample returnSample returnA sample return mission collects rock, soil or dust from another world and brings it back to Earth to study in labs.More in the glossary mission: a lander will collect rock and soil, and a chain of spacecraft will carry them to Earth.[1][11] CNSA said in April 2026 that it will launch around 2028 on two Long March 5 rockets from the Wenchang Space Launch Center on Hainan island, and bring the samples to Earth around 2031.[1] The aim is to return at least 500 g (about 1.1 lb), the mission’s chief scientist, Hou Zengqian, and colleagues wrote in Nature Astronomy in June 2025.[3] If it works, CNSA says, it will be the first mission to bring material from Mars to Earth.[1]

Its top science goal is to look for signs of life, past or present.[3][8] In September 2026 Hou told Xinhua that the mission had entered the stage of developing engineering prototypes.[8]

Tianwen-3 follows Tianwen-1, China’s first mission to another planet, which landed the Zhurong rover in May 2021. On landing day, Tianwen-1’s chief planner, Zhang Rongqiao, said China had started planning a sample return.[12]

How will Tianwen-3 bring samples back?

In stages: land, collect samples, launch them into Mars orbit, hand them to an orbiter and send a capsule home.[5][11] CNSA lists five parts: a lander, an ascent vehicle (its “ascender”), a service module, an orbiter and a return module.[1][6] Its 2025 call for partners described two linked spacecraft: a lander, ascender and Mars orbiter, and an Earth-return orbiter with a reentry module.[2]

The trip out should take seven to eight months. The spacecraft would then spend about a year at Mars before heading home, more than three years in all, Hou said in July 2025, Xinhua reported.[5] Chief designer Liu Jizhong has called it the most technically challenging space mission since Apollo, and the plan has 13 phases.[5][13] The engineering team has a preliminary design for three ways to collect samples:[5]

• 01A scoop. Material scooped up from the surface.[5]
• 02A drill. Samples drilled from about 2 m (6.6 ft) down.[5]
• 03A drone, not a rover. Hou said Tianwen-3 will carry no rover. Instead, a drone will collect samples from within several hundred meters of the landing site.[5]
• 04One site. The landing site is also the sampling site, China Daily reported in 2024, citing China’s Deep Space Exploration Laboratory.[10]

CNSA’s 2025 call also gave the planned orbits. The Mars orbiter is to fly a long ellipse, 400 km by 76,000 km (250 mi by 47,000 mi) above Mars, and observe for two years. The Earth-return orbiter is to circle 350 km (217 mi) up.[2]

Back on Earth, the mission’s scientists propose handling the samples under the Committee on Space Research’s planetary protection policy, in a Mars Sample Laboratory that would also protect Earth from any possible Martian life.[3] In August 2026 Xinhua reported that a planetary protection laboratory will be built in Hefei’s Deep-Space Science City, in Anhui province, to sterilize, open and process the samples and assess any biological risk.[9]

Where will Tianwen-3 land?

The site hasn’t been chosen yet; Hou told Xinhua in September 2026 that China expects to finalize it by the end of 2026.[8] The engineering limits are strict: between 17° and 30°N, at an elevation of −3 km (−1.9 mi) or lower, on slopes of 8° or less, with rocks covering no more than 10% of the ground.[4]

In October 2024 the science team proposed 86 possible sites, mostly in Chryse Planitia and Utopia Planitia. They include ancient coastlines, deltas, lakes and canyon systems.[4][10] By July 2025 the list was down to 19, Hou said, with three finalists to be picked by the end of 2026. The winner should be the site most likely to have held, and preserved, traces of life.[5] Zhurong, China’s first rover, landed in southern Utopia Planitia.[9]

What will Tianwen-3 carry?

CNSA’s 2025 plan listed six Chinese science instruments, and in April 2026 it picked five more from Hong Kong, Macao and international teams.[1][2] In 2025 CNSA set aside 20 kg (44 lb) on the spacecraft for partners; it received 28 applications, Xinhua reported.[13][6]

From CNSA’s English site, Xinhua and CGTN. CNSA’s page puts the hyperspectral imager on the orbiter; Xinhua and CGTN put it on the service module.[1][6][7]

The six Chinese instruments in CNSA’s 2025 plan: a subsurface radar and a Raman and fluorescence analyzer on the lander; a detector for energetic neutral atoms and auroras, and a magnetometer, on the Mars orbiter; and a mid-infrared hyperspectral imager and a multispectral camera on the Earth-return orbiter.[2]

How does Tianwen-3 compare with NASA’s Mars Sample Return?

Tianwen-3 would collect its own samples and fly them home in one mission; NASA’s plan was to fetch samples Perseverance has already collected, and Congress has declined to fund it.[10][14][17] NASA and ESA’s campaign needed a lander near Perseverance’s landing site in Jezero Crater, a small rocket to launch the samples into Mars orbit, and ESA’s Earth Return Orbiter to catch them there and bring them home.[14][16] In April 2024 NASA said the design then on the table would cost $8 billion to $11 billion and return samples in 2040.[15] The FY2026 spending agreement, signed into law on Jan 23, 2026, “does not support the existing Mars Sample Return (MSR) program.”[17][18]

Plans as stated by CNSA, Tianwen-3’s scientists and NASA. NASA studied two cheaper landing options in 2025 before its funding ended.[1][3][8][14][15][16][17]

The full story of NASA’s plan is on our Mars Sample Return page.

Mission timeline

1. May 15, 2021As Tianwen-1 lands, its chief planner says China has started planning a Mars sample return.[12]
2. March 2022CNSA’s Wu Weiren outlines the steps: land, collect, launch to an orbiter, return.[11]
3. October 2024The science team publishes 86 possible landing sites.[4]
4. April 2025CNSA invites international partners and sets aside 20 kg for their instruments.[13][6]
5. June 2025The mission’s scientists set out its plan in Nature Astronomy.[3]
6. July 2025The landing site list is down to 19, the chief scientist says.[5]
7. Apr 24, 2026CNSA names five partner instruments.[1][6]
8. August 2026Plans for a planetary protection lab in Hefei are reported.[9]
9. September 2026The mission is building engineering prototypes, its chief scientist says.[8]
10. By end of 2026China’s target for choosing the landing site.[8]
11. 2027Partner instruments’ flight models are due.[2]
12. Around 2028China’s target for the two launches.[1]
13. Around 2031China’s target for the samples to reach Earth.[1][3]

CNSA’s 2025 call for partners gave around 2030 for the return; the mission’s scientists (June 2025) and CNSA (April 2026) have since said around 2031.[2][1][3] Our launch windows page shows when the 2028 window opens.

Sources

1. China National Space Administration (CNSA) — China celebrates Space Day with a sneak peek at Tianwen 3’s tech (Apr 24, 2026, from China Daily)Primary · checked Oct 6, 2026
2. China National Space Administration (CNSA) — Announcement of Opportunities for International Collaboration of Mars Sample Return Mission (Tianwen-3)Primary · checked Oct 6, 2026
3. Nature Astronomy — In search of signs of life on Mars with China’s sample return mission Tianwen-3 (Hou et al., Nature Astronomy, 2025)Primary · checked Oct 6, 2026
4. National Science Review — The search for life signatures on Mars by the Tianwen-3 Mars sample return mission (Hou et al., National Science Review, 2024)Primary · checked Oct 6, 2026
5. Xinhua — China Focus: Chinese scientist details first planned Mars sample-return mission Tianwen-3Secondary · checked Oct 6, 2026
6. Xinhua — Update: China unveils international partners for Tianwen-3 Mars missionSecondary · checked Oct 6, 2026
7. CGTN — China unveils Tianwen-3 plans in search for life on MarsSecondary · checked Oct 6, 2026
8. Xinhua — Chief scientist of China’s Tianwen-3 mission says search for signs of life on Mars is top goalSecondary · checked Oct 6, 2026
9. Xinhua — China to build planetary protection lab for Mars sample-return missionSecondary · checked Oct 6, 2026
10. China Daily — China plans to retrieve Martian samples around 2031: laboratorySecondary · checked Oct 6, 2026
11. China National Space Administration (CNSA) — Challenges await sample-return expedition to Mars (Mar 11, 2022)Primary · checked Oct 6, 2026
12. China National Space Administration (CNSA) — Probe makes historic landing on Mars (May 17, 2021)Primary · checked Oct 6, 2026
13. China National Space Administration (CNSA) — China deepens international collaboration to push forward deep-space exploration (Apr 25, 2025, from Xinhua)Primary · checked Oct 6, 2026
14. NASA Science — Mars Sample ReturnPrimary · checked Oct 6, 2026
15. NASA — NASA Sets Path to Return Mars Samples, Seeks Innovative DesignsPrimary · checked Oct 6, 2026
16. NASA — NASA to Explore Two Landing Options for Returning Samples from MarsPrimary · checked Oct 6, 2026
17. House Appropriations Committee — Division A – Commerce, Justice, Science: Joint Explanatory Statement (Mars Sample Return, p. 54)Primary · checked Oct 6, 2026
18. GovInfo — Public Law 119-74 (H.R. 6938, FY2026 appropriations)Primary · checked Oct 6, 2026