Tianwen-1

Tianwen-1 Chinese: 天问一号 (also referred to as TW-1; simplified Chinese: 天问; traditional Chinese: 天問; lit. 'Heavenly Questions'') is an interplanetary mission by the China National Space Administration (CNSA) which sent a robotic spacecraft to Mars, consisting of 6 spacecraft: an orbiter, two deployable cameras, lander, remote camera, and the Zhurong rover. The spacecraft, with a total mass of nearly five tons, is one of the heaviest probes launched to Mars and carries 14 scientific instruments. It is the first in a series of planned missions undertaken by CNSA as part of its Planetary Exploration of China program.

The mission's scientific objectives include: investigation of Martian surface geology and internal structure, search for indications of current and past presence of water, and characterization of the space environment and the atmosphere of Mars.

The mission was launched from the Wenchang Spacecraft Launch Site on 23 July 2020 on a Long March 5 heavy-lift launch vehicle. After seven months of transit through the inner Solar System, the spacecraft entered Martian orbit on 10 February 2021. For the next three months the probe studied the target landing sites from a reconnaissance orbit. On 14 May 2021, the lander/rover portion of the mission successfully touched down on Mars, making China the third nation to make a soft landing on and establish communication from the Martian surface, after the Soviet Union and the United States.

On 22 May 2021, the Zhurong rover drove onto the Martian surface via the descent ramps on its landing platform. With the successful deployment of the rover, China became the second nation to accomplish this feat, after the United States. In addition, China is the first nation to carry out an orbiting, landing and rovering mission on Mars successfully on its maiden attempt. Tianwen-1 is also the second mission to capture audio recordings on the Martian surface, after United States' Perseverance rover. The "smallsat" deployed by the Zhurong rover on the Martian surface consists of a "drop camera" which photographed both the rover itself as well as the Tianwen-1 lander. With a mass of less than 1 kg, the Tianwen-1 remote camera is the lightest artificial object on Mars as of May 2021. On December 31, 2021, the Tianwen-1 orbiter deployed a second deployable camera (TDC-2) into Mars orbit which captured photographs of the Tianwen-1 in orbit to celebrate its achievement of the year and a selfie stick payload was deployed to its working position on orbiter to take images of the orbiter's components and Chinese flag on 30 January 2022 to celebrate the Chinese New Year. In September 2022, the mission was awarded the World Space Award by the International Astronautical Federation.

The Tianwen-1 mission was the second of three Martian exploration missions launched during the July 2020 window, after the United Arab Emirates Space Agency's Hope orbiter, and before NASA's Mars 2020 mission, which landed the Perseverance rover with the attached Ingenuity helicopter drone.