Mars Global Remote Sensing Orbiter and Small Rover (2020).png
Tianwen-1 undergoing tests in 2019. The silver capsule on top houses the lander and rover, and the gold bottom half with the rocket engine is the orbiter.
NamesHuoxing-1 (火星-1) (2018–2020)[1][2][3]
Mission typePlanetary science with an orbiter, lander and rover
COSPAR ID2020-049A
SATCAT no.45935
Mission duration131 days, 18 hours, 14 minutes (since launch)
Orbiter: 2 Earth years (planned)
Rover: 90 sols (planned)[4]
Spacecraft properties
Spacecraft typeOrbiter, lander, rover
ManufacturerChina Aerospace Science and Technology Corporation (CASC)
Launch massTotal: 5,000 kg (11,000 lb)
Orbiter: 3,175 kg (7,000 lb)
Rover:240 kg (530 lb)
DimensionsRover: 2.0 × 1.65 × 1.85 metres
Start of mission
Launch date23 July 2020, 04:41:15 UTC [5]
RocketLong March 5
Launch siteWenchang, LC-101
ContractorChina Aerospace Science and Technology Corporation
Mars orbiter
Spacecraft componentOrbiter
Orbital insertion11 to 24 February 2021 (planned)[6]
Mars lander
Spacecraft componentLander
Landing date23 April 2021[6] (proposed)
Landing siteUtopia Planitia[7]
Mars rover
Spacecraft componentRover
Landing dateAfter 23 April 2021[6] (proposed)
Landing siteUtopia Planitia[7]
Chinese Planetary Exploration Mars logo
Chinese Planetary Exploration
(Chinese: 中国行星探测) Mars logo  

Tianwen-1 (TW-1) is an interplanetary mission to Mars by the China National Space Administration (CNSA) to send a robotic spacecraft, which consists of an orbiter, deployable camera, lander and a rover.[8] The mission was successfully launched from the Wenchang Spacecraft Launch Site on 23 July 2020[9] with a Long March 5 heavy-lift rocket, and is currently en route to Mars, having already traveled 29.4 million kilometers as of 9 October, 2020. Tianwen has so far completed two mid-course orbital corrections and performed self diagnostics on multiple payloads.[10] The spacecraft has begun to conduct scientific operations with the Mars Energetic Particle Analyzer, mounted on the orbiter, which has already transmitted data back to ground control.[11] Its objectives are to search for evidence of both current and past life, and to assess the planet's environment.[4][12]

The name "Tianwen" (simplified Chinese: 天问; traditional Chinese: 天問; lit.: 'heavenly questions') comes from the long poem of the same name written by Qu Yuan (about 340–278 BC), one of the greatest poets of Ancient China.[13] It is a poem of a series of questions starting with how the universe was created.

Tianwen-1 was the second of three space missions sent toward Mars during the July 2020 Mars launch window, with missions also launched by the national space agencies of the United Arab Emirates (Hope orbiter) and the United States (Mars 2020, with the Perseverance rover and an attached helicopter drone). All three are expected to arrive at Mars in February 2021.

In September, Tianwen-1 deployed[14] the TW-1 Deployable Camera (T.D.C.), a small satellite with two cameras that took photos of and tested a Wi-Fi connection with Tianwen-1.


Tianwen-1 Launch - 23 July 2020, 04:41:15 UTC

China's Mars program started in partnership with Russia. In November 2011, the Russian spacecraft Fobos-Grunt, destined for Mars and Phobos, was launched from Baikonur Cosmodrome. The Russian spacecraft carried with it an attached secondary spacecraft, the Yinghuo-1, which was intended to become China's first Mars orbiter (Fobos-Grunt also carried experiments from The Planetary Society and Bulgaria). However, Fobos-Grunt's main propulsion unit failed to boost the Mars-bound stack from its initial Earth parking orbit and the combined multinational spacecraft and experiments eventually reentered Earth's atmosphere in January 2012[15]. China subsequently began an independent Mars project[16] and the current mission, which was formally approved by Chinese authorities in early 2016[17], is the result.[citation needed]

The new Chinese Mars spacecraft, consisting of an orbiter and a lander with an attached rover, is developed by the China Aerospace Science and Technology Corporation (CASC) and managed by the National Space Science Centre (NSSC) in Beijing.[11] The lander portion of the spacecraft will use a parachute and a retrorocket in order to achieve landing on the Martian surface.[18] If the landing is successful, the lander would then release a rover. This rover will be powered by solar panels and is expected to probe the Martian surface with radar and to perform chemical analyses on the soil; it would also look for biomolecules and biosignatures.[4]

The TW-1 Deployable Camera (T.D.C.) deployed from the orbiter in September while en route to Mars. Its mission was to photograph the Tianwen-1 orbiter and aeroshell. It took two photos, the T.D.C. spacecraft will fly by Mars.[citation needed]

Scientific objectives

The aims of the mission may include the following: find evidence for current and past life, produce Martian surface maps, characterize Martian soil composition and water ice distribution, examine the Martian atmosphere, and in particular, its ionosphere, among others.[19] Simulated Martian landings have been performed as part of mission preparations by the Beijing Institute of Space Mechanics and Electricity.[8]

The current Mars mission also would serve as a demonstration of technology that will be needed for an anticipated Chinese Mars sample-return mission proposed for the 2030s.[11] There was also a plan that involved using the current mission to cache Martian rock and soil samples for retrieval by the later sample-return mission.[20]

Mission planning

Planned orbital trajectory at Mars.
Tianwen-1 transfer orbit and trajectory correction maneuvers (TCM).
Map of Mars with the two possible landing areas of Tianwen-1, and the locations of previous Mars landings.

In late 2019, the Xi'an Aerospace Propulsion Institute, a subsidiary of CASC, stated that the performance and control of the future spacecraft's propulsion system has been verified and had passed all requisite pre-flight tests, including tests for hovering, hazard avoidance, deceleration, and landing. The main component of the lander's propulsion system consists of a single engine that provides 7500 newtons of thrust. The spacecraft's supersonic parachute system had also been successfully tested previously.[17]

CNSA initially focused on the Chryse Planitia and on the Elysium Mons regions of Mars in its search for possible landing sites for the lander and its associated rover. However, in September 2019, during a joint meeting in Geneva of the European Planetary Science Congress-Division for Planetary Sciences, Chinese presenters announced that two preliminary sites in the Utopia Planitia region of Mars have instead been chosen for the anticipated landing attempt, with each site having a landing ellipse of approximately 100 by 40 kilometres.[17]

In July 2020, CNSA provided landing coordinates of 110.318 degrees east longitude and 24.748 degrees north latitude, within the southern portion of Utopia Planitia as the specific primary landing site. The area appears to provide a relatively safe place for a landing attempt but is also of great scientific interest, according to Alfred McEwen, director of the Planetary Image Research Laboratory at the University of Arizona.[7]

By 23 January 2020 the Long March 5 Y4 rocket's hydrogen-oxygen engine had completed a 100-seconds test, which was the last engine test prior to the final assembly of the carrier rocket. It successfully launched on 23 July 2020.[21]

Scientific instruments

Mockup of the rover at the 69th International Astronautical Congress

To achieve the scientific objectives of the mission, the Tianwen-1 orbiter and rover are equipped with 13 instruments:[22]

  • Medium Resolution Camera (MRC) with a resolution of 100 m from a 400 km orbit[8]
  • High Resolution Camera (HRC) with a resolution of 2 m from a 400 km orbit[citation needed]
  • Mars Magnetometer (MM)[citation needed]
  • Mars Mineralogy Spectrometer (MMS), to determine elementary composition[citation needed]
  • Orbiter Subsurface Radar (OSR)[citation needed]
  • Mars Ion and Neutral Particle Analyzer (MINPA)[6]
  • Mars Energetic Particle Analyzer [22]
  • Ground-Penetrating Radar (GPR), to image about 100 metres (330 ft) below the Martian surface[12]
  • Mars Surface Magnetic Field Detector (MSMFD)[citation needed]
  • Mars Meteorological Measurement Instrument (MMMI)[citation needed]
  • Mars Surface Compound Detector (MSCD)[citation needed]
  • Multi-Spectrum Camera (MSC)[citation needed]
  • Navigation and Topography Camera (NTC)[6]

International collaborations


Argentina's CONAE is collaborating on Tianwen-1 by way of a Chinese-run tracking station installed in Las Lajas, Neuquén. The facility played a previous role in China's landing of the Chang'e-4 spacecraft on the far side of the moon in January 2019.[24]

France's Institute for Research in Astrophysics and Planetology (IRAP) in Toulouse is collaborating on the Tianwen-1 rover. Sylvestre Maurice of IRAP said, "For their Laser Induced Breakdown Spectroscopy (LIBS) instrument, we have delivered a calibration target that is a French duplicate of a target which is on NASA's Curiosity Mars rover. The idea is to see how the two datasets compare."[24]

Austria's Austrian Research Promotion Agency (FFG) aided in the development of a magnetometer installed on the Chinese Mars orbiter. The Space Research Institute of the Austrian Academy of Sciences in Graz has confirmed the group's contribution to the Tianwen-1 magnetometer and helped with the calibration of the flight instrument.[24]

Acheron FossaeAcidalia PlanitiaAlba MonsAmazonis PlanitiaAonia PlanitiaArabia TerraArcadia PlanitiaArgentea PlanumArgyre PlanitiaChryse PlanitiaClaritas FossaeCydonia MensaeDaedalia PlanumElysium MonsElysium PlanitiaGale craterHadriaca PateraHellas MontesHellas PlanitiaHesperia PlanumHolden craterIcaria PlanumIsidis PlanitiaJezero craterLomonosov craterLucus PlanumLycus SulciLyot craterLunae PlanumMalea PlanumMaraldi craterMareotis FossaeMareotis TempeMargaritifer TerraMie craterMilankovič craterNepenthes MensaeNereidum MontesNilosyrtis MensaeNoachis TerraOlympica FossaeOlympus MonsPlanum AustralePromethei TerraProtonilus MensaeSirenumSisyphi PlanumSolis PlanumSyria PlanumTantalus FossaeTempe TerraTerra CimmeriaTerra SabaeaTerra SirenumTharsis MontesTractus CatenaTyrrhen TerraUlysses PateraUranius PateraUtopia PlanitiaValles MarinerisVastitas BorealisXanthe TerraMap of Mars
The image above contains clickable linksInteractive image map of the global topography of Mars, overlain with locations of Mars landers and rovers. Hover your mouse over the image to see the names of over 60 prominent geographic features, and click to link to them. Coloring of the base map indicates relative elevations, based on data from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor. Whites and browns indicate the highest elevations (+12 to +8 km); followed by pinks and reds (+8 to +3 km); yellow is 0 km; greens and blues are lower elevations (down to −8 km). Axes are latitude and longitude; Polar regions are noted.
(See also: Mars map, Mars Memorials, Mars Memorials map) (view • discuss)
(   Active Rover  Acrtive Lander  Future )
Beagle 2
Bradbury Landing
Deep Space 2
Columbia Memorial Station
InSight Landing
Mars 2020
Mars 2
Mars 3
Mars 6
Mars Polar Lander
Challenger Memorial Station
Green Valley
Schiaparelli EDM lander
Carl Sagan Memorial Station
Columbia Memorial Station
Thomas Mutch Memorial Station
Gerald Soffen Memorial Station

See also


  1. ^ "中国火星探测器露真容 明年发射". 12 October 2019.
  2. ^ The Global Exploration Roadmap. NASA International Space Exploration Coordination Group. January 2018 This article incorporates text from this source, which is in the public domain.
  3. ^ China's Deep Space Exploration Roadmap. 2018.
  4. ^ a b c "China Exclusive: China's aim to explore Mars". Xinhua News. 21 March 2016. Retrieved 24 March 2016.
  5. ^ Wall, Mike. "China launches ambitious Tianwen-1 Mars rover mission". Space.com.
  6. ^ a b c d e 2020中国火星探测计划(根据叶院士报告整理 Published in 2018.
  7. ^ a b c Andrew Jones 28 October 2020. "China chooses landing site for its Tianwen-1 Mars rover". Space.com. Retrieved 16 November 2020.
  8. ^ a b c Jones, Andrew (9 February 2018). "China simulates Mars landing in preparation for 2020 mission". GBTimes. Retrieved 3 March 2018.
  9. ^ Jones, Andrew (23 July 2020). "Tianwen-1 launches for Mars, marking dawn of Chinese interplanetary exploration". spacenews.com. Retrieved 23 July 2020.
  10. ^ "China's Mars probe completes deep-space maneuver - Xinhua | English.news.cn". www.xinhuanet.com. Retrieved 10 October 2020.
  11. ^ a b c Jones, Andrew (22 February 2016). "China is racing to make the 2020 launch window to Mars". GBTimes. Retrieved 22 February 2016.
  12. ^ a b The subsurface penetrating radar on the rover of China's Mars 2020 mission. B. Zhou, S. X. Shen, Y. C. Ji, etal. 2016 16th International Conference on Ground Penetrating Radar (GPR). 13–16 June 2016.
  13. ^ "China's First Mars Exploration Mission Named Tianwen-1". XinhuaNet. 24 April 2020. Retrieved 24 April 2020.
  14. ^ "Send blessings to the sky, and the full moon welcomes the birthday——Tianwen No.1 blessed the 71st birthday of the motherland with a "selfie flag"".
  15. ^ Zolotukhin, Alexei (15 January 2012). "Russian Phobos-Grunt Mars probe falls in Pacific Ocean". RIA Novosti. Retrieved 16 January 2012. Phobos-Grunt fragments have crashed down in the Pacific Ocean
  16. ^ Nan, Wu (24 June 2014). "Next stop – Mars: China aims to send rover to Red Planet within six years". South China Morning Post. Retrieved 23 February 2016.
  17. ^ a b c Jones, Andrew (8 November 2019). "China Says Its Mars Landing Technology Is Ready For 2020". IEEE Spectrum. Retrieved 30 December 2019.
  18. ^ Jones, Andrew (21 March 2016). "China reveals more details of its 2020 Mars mission". GB Times. Retrieved 22 March 2016.
  19. ^ Zhou; et al. (13–16 June 2016). "The subsurface penetrating radar on the rover of China's Mars 2020 mission". 2016 16th International Conference on Ground Penetrating Radar (GPR). pp. 1–4. doi:10.1109/ICGPR.2016.7572700. ISBN 978-1-5090-5181-6. S2CID 306903.
  20. ^ China Plans To Land A Rover On Mars In 2020. Alexandra Lozovschi, Inquisitr. January 17, 2019.
  21. ^ Tianwen-1 launch
  22. ^ a b "China launches robotic mission to orbit, land, and drive on Mars". Spaceflight Now. 23 July 2020. Retrieved 24 July 2020.
  23. ^ Tianwen-1 Mars Rover and Lander
  24. ^ a b c David, Leonard (22 July 2020). "China's Tianwen-1 Mars rover mission gets a boost from international partners". Space.com. Retrieved 10 September 2020.