Everything We Know About China's First Rover Mission to Mars

China successfully launched its first rover mission to Mars on Thursday.

At 12:41 a.m. local time, a Long March 5 rocket blasted off from Wenchang Satellite Launch Site on Hainan Island—China's southernmost point—carrying the five-tonne Tianwen-1 probe, which comprises an orbiter and lander/rover pair.

The Tianwen-1 (meaning "Questions to Heaven") spacecraft is scheduled to arrive at the red planet in February 2021. However, the lander/rover won't try and touch down straight away.

Instead, it will wait 2-3 months to perform a soft landing on the Martian surface, with China National Space Administration (CNSA) operators targeting a site within a region known as Utopia Planitia, according to an article in the journal Nature Astronomy written by members of the mission team.

Utopia Planitia is a vast plain located north of the planet's equator. It is the largest known impact basin in the solar system, with an estimated diameter of more than 2,000 miles.

After separating from the orbiter, the lander/rover is designed to make a controlled descent using a parachute and retro-rocket boosters. Upon touchdown, a ramp will be deployed, enabling the rover to drive out into the plain.

Once deployed on the surface, the 550-pound, solar-powered rover is expected to remain in operation for about 90 sols, or Martian days—which are around 40 minutes longer than days on Earth—collecting scientific data using six different instruments. If everything goes to plan, the scientific observation stage will begin in April 2021.

The orbiter meanwhile will remain in an elliptical orbit around Mars, coming as close as 165 miles to the planet and reaching as far away as 7,456 miles. The spacecraft will act as a relay communication link to the rover, and is equipped with seven scientific instruments of its own, enabling it to conduct observations from above.

According to the Nature Astronomy paper, the main goal of the Tianwen-1 mission is "to perform a global and extensive survey of the entire planet using the orbiter, and to send the rover to surface locations of scientific interests to conduct detailed investigations with high accuracy and resolution."

This goal will include mapping the shape and geological structure of the planet; investigating the characteristics of the surface soil and the distribution of water ice; analyzing the material composition of the surface; taking measurements of the Martian climate and environment; and collecting data on the planet's electromagnetic and gravitational fields, as well as its internal structure.

"Tianwen-1 is going to orbit, land and release a rover all on the very first try, and coordinate observations with an orbiter. No planetary missions have ever been implemented in this way. " the Tianwen-1 team members wrote in the Nature paper. "If successful, it would signify a major technical breakthrough. Scientifically, Tianwen-1 is the most comprehensive mission to investigate the Martian morphology, geology, mineralogy, space environment, and soil and water-ice distribution."

China Tianwen-1 Mars mission
A Long March-5 rocket, carrying an orbiter, lander and rover as part of the Tianwen-1 mission to Mars, lifts off from the Wenchang Space Launch Center in southern China's Hainan Province on July 23, 2020. NOEL CELIS/AFP via Getty Images

"Among the eight planets in the solar system, Mars is the most similar to Earth and is also close by. It therefore naturally becomes a high-priority target for space exploration," they wrote. "Mars offers a substantial and pragmatic opportunity to answer key questions concerning the existence of extraterrestrial life, and the origin and evolution of the Solar System, and to explore the possibility of human habitation."

The mission—whose name is taken from a poem written by Qu Yuan, one of ancient China's greatest poets—is ambitious for a first Mars rover mission. However, CNSA will take heart from two recent successful moon landings, which formed part of its "Chang'e" lunar exploration program. To date, only the U.S. has successfully conducted long-term rover missions on the red planet.

Technically, Tianwen-1 is not China's first Mars mission. In November, 2011, CNSA launched the Yinghuo-1 orbiter, which was intended to be the first Chinese spacecraft to orbit Mars. The orbiter was launched alongside Russia's Fobos-Grunt spacecraft, however, the launch failed, leaving both probes stranded in orbit.

Remarkably, Tianwen-1 is one of three Mars missions to launch this month. Earlier the week the United Arab Emirates successfully launched its Hope Mars orbiter. And next week, NASA is set to launch its Mars 2020 Perseverance rover.

"The international planetary science community looks forward to these exciting missions, which will certainly advance our knowledge of Mars to an unprecedented level," the Tianwen-1 team members wrote.