What did Tianwen-1 gain from "Detecting Fire" in one year?

  On May 15, 2021, China's first Mars exploration mission, the Tianwen-1 probe, successfully landed on Mars, leaving China's mark on Mars for the first time.

For more than a year, Tianwen-1's every move has attracted worldwide attention from launch, orbiting, landing, and inspection.

  Up to now, the Zhurong rover has been driving for more than a year in the Utopia Plain in the northern lowland of Mars, and has traveled nearly 2,000 meters in total, obtaining a large amount of valuable scientific exploration data.

One year of "fire detection", what did Tianwen-1 gain?

How far will China's deep space exploration go in the near future?

  Zhurong Mars Rover:

  Continuous "service" and temporary "hibernation"

  According to information released by the China National Space Administration recently, since Tianwen-1 landed on Mars for a year, the Zhurong rover has worked on the surface of Mars for 356 Martian days, with a total mileage of 1,921 meters.

The orbiter has flown for 661 days since its launch, and has continued to carry out remote sensing detection after entering the orbit around the fire.

At present, the two devices are in good condition, accumulatively acquiring and returning about 940GB of original scientific data.

  In the history of China's aerospace development, the Tianwen-1 mission has achieved 6 "firsts": the first launch of a ground-fire transfer orbital probe; the first interplanetary flight; the first soft landing on an extraterrestrial planet; Exploration; for the first time, the measurement and control communication at a distance of 400 million kilometers was realized; for the first time, the first-hand Mars scientific data was obtained.

  After setting foot on Mars, the Zhurong rover has gone through multiple tests.

After completing 90 Mars-day inspection missions, the Zhurong Mars rover passed the solar transit phase, when the sun moved between the earth and Mars, and was disturbed by the electromagnetic radiation of the sun, and the communication between the vehicle and the ground was unstable.

According to the established plan, the rover will suspend scientific work during the solar transit.

After the Sun Ling, the "extended service" Zhurong Mars rover continued to carry out extended inspection and exploration missions, obtaining topographic and landform images of the inspection area, magnetic field information of the driving path, and subsurface profile structure information, as well as the composition information of typical features such as rocks and dunes, and First-hand scientific data such as temperature, air pressure, wind direction, wind speed and meteorological information, to explore clues to the mystery of the origin and evolution of Mars.

  Entering 2022, Tianwen-1 sent back "greetings" and good news one after another, leaving many unforgettable moments - on the eve of the Spring Festival of the Year of the Tiger in the lunar calendar, Tianwen-1 sent back a set of "selfie" videos from the orbit of Mars for New Year's greetings; Beijing On the opening day of the Winter Olympics, the Tianwen-1 probe was framed with the five-star red flag and the emblems of the Winter Olympics and Paralympics... The release of a series of "beautiful photos" and scientific images gave the public a better understanding of the mysterious Mars. Learn more and know more.

  According to experts, the inspection area of ​​the Zhurong Mars rover has entered winter. The maximum temperature during the day has dropped to below minus 20 degrees Celsius, and the minimum temperature at night has dropped to minus 100 degrees Celsius. By mid-July, around the Mars winter solstice, the temperature will drop further. .

At the same time, the Tianwen-1 mission team judged and analyzed the medium-resolution images obtained by the orbiter, and the area where Zhurong is located is experiencing strong sand and dust weather.

  In order to cope with the reduction in the power generation capacity of the solar wing caused by the dusty weather and the extremely low ambient temperature in winter, according to the design plan and flight control strategy, the Zhurong rover entered the dormant mode on May 18.

It is expected that around December this year, the inspection area will enter the early spring season. After the environmental conditions improve, Zhurong will resume normal work.

During this period, the orbiter will continue to carry out remote sensing exploration and provide relay communication support for the rover.

  Detection results:

  Spot signs of recent water activity

  For more than a year since Tianwen-1 landed on Mars and Zhurong traveled on Mars, the China National Space Administration has released ten batches of Tianwen-1 scientific exploration data.

Scientists have successively released new scientific discoveries and scientific research results through the study of detection data.

  Recently, the Chinese Academy of Sciences announced a research result - Liu Yang's team from the National Space Science Center of the Chinese Academy of Sciences discovered a lithified plate-like hard crust in the Mars landing area with a relatively young geological age, which is rich in minerals such as hydrous sulfate. , the formation process may be related to groundwater fluctuations.

  How did Mars evolve from an 'ocean planet' to a 'desert planet'?

The evolution of water environment on Mars is one of the important contents of Mars research.

According to Liu Yang, the Zhurong rover's landing area is located on the young Amazonian strata—the Amazonian from 3 billion years ago to the present is the end of several major stages of the Martian geological age.

Existing studies believe that Mars was cold and dry during the Amazonian period, and the scope and extent of liquid water activity were extremely limited.

  Using data from the Zhurong rover, the research team found a lithified plate-like crust, which is rich in minerals such as hydrous sulfate.

It is inferred that these hard crusts may be formed by lithification after cementing the Martian soil and salt minerals crystallized by groundwater overflow or capillary evaporation.

  Liu Yang said the discovery means that water activity on Mars in the Amazonian period may have been more active than previously thought, and the Zhurong landing area and the extensive area of ​​the northern plain of Mars may contain a large amount of available water in the form of hydrous minerals, which can be used for water. In situ resource utilization for future manned Mars exploration.

This discovery has important implications for understanding the evolutionary history of the climate and environment of Mars.

  Planetary Exploration:

  Asteroid detection and sampling in the future

  According to the white paper "2021 China's Spaceflight", in the next five years, China will continue to implement planetary exploration projects, launch asteroid probes, complete near-Earth asteroid sampling, and complete key technological breakthroughs such as Mars sampling and return.

  According to the plan, China will also successively implement tasks such as Tianwen-2, Tianwen-3, and Tianwen-4.

According to the Fifth Academy of China Aerospace Science and Technology Corporation, the Tianwen-2 probe has been transferred to the initial sample development stage, and the mission is accelerating.

  Wu Weiren, academician of the Chinese Academy of Engineering and chief designer of China's lunar exploration project, said that China's deep space exploration will continue for a long time, "as fast as it can go, as far as it can go."

The main follow-up task is to detect asteroids in far-reaching space, hoping to sample asteroids and become a country with asteroid samples.

  Zhang Rongqiao, chief designer of China's first Mars exploration mission, said that in addition to the significance of scientific research, the asteroid exploration mission will also verify relevant technologies for subsequent Mars sampling returns through the progressive development of technology.

  The return of Mars sampling can be described as the "jewel in the crown" of Mars exploration, and no country has yet done it.

Zhang Rongqiao said that compared with the return of samples from the moon, there are many difficulties in the return of samples from Mars - the "size" of Mars is much larger than that of the moon, and a larger escape velocity is required for take-off and return from Mars, which requires the rocket to have stronger power. There is an atmosphere on the surface of Mars, and taking off from the surface of Mars requires a complete set of flight products and their control systems adapted to the Martian atmospheric environment; coupled with the long journey to and from Mars, and the harsh environment of Mars, it increases the difficulty of sampling and returning.

  Wu Weiren said that in the future, China is also preparing to conduct traversal and exploration of other planets in the solar system, such as the detection of Venus and the near-Earth asteroids that threaten the earth, so as to realize their early warning, defense, and disposal.

  China's planetary exploration project is open, and China has always been committed to promoting international cooperation in the field of deep space exploration.

During the implementation of the Tianwen-1 mission, China has carried out fruitful cooperation with relevant countries and international organizations in measurement and control support, payload development, and scientific research.

  Among them, China and ESA have carried out engineering and technical cooperation, and the Zhurong Mars rover and ESA's "Mars Express" orbiter have succeeded in the on-orbit relay communication test; carried out scientific payload cooperation with Austria and France; The deep space station is China's first overseas deep space measurement and control station, providing measurement and control support for Tianwen-1; China has also established a Mars probe orbit data exchange mechanism with the United States, and launched international payload carrying cooperation for asteroid exploration missions.

Liu Yao

Liu Yao

Keywords: