China News Agency, Beijing, April 26 (Reporter Sun Zifa) Chinese officials have recently announced that the Chinese planetary exploration mission is named "Tianwen" series, and the first Mars exploration mission to be carried out in 2020 will be named "Tianwen 1" , Triggering a wave of attention.
The ground application system of the first Mars exploration project undertaken by the National Astronomical Observatory of the Chinese Academy of Sciences was successfully implemented in Tianjin on the 25th to complete the overall lifting of the 70-meter antenna reflector, which attracted much attention. Li Chunlai, deputy director of the National Astronomical Observatory of the Chinese Academy of Sciences and deputy chief designer of China ’s first Mars exploration project and chief commander of the ground application system, interpreted on March 26, revealing that the 70-meter antenna can be completely completed in October this year. It has the data receiving capability of Mars exploration.
Why China's planetary exploration first explored Mars
According to the plan, China will implement the first Mars exploration mission in 2020. The goal is to achieve a Mars orbit and landing patrol through a launch mission, conduct global and comprehensive exploration of Mars, and conduct patrol surveys on key areas on the surface of Mars.
Why did you choose Mars as the first station of China's planetary exploration? Li Chun said that Mars is one of the planets in the solar system that is close to the earth and the natural environment is most similar to the earth. It has always been a hot spot for human exploration in deep space. Since 1961, humans have conducted Mars exploration activities 45 times, but only 22 successful and partially successful missions. "It can be said that apart from the moon, Mars is the most concerned object."
He believes that China's first independent Mars exploration is not only to explore the existence and evolution of Mars life, but also to understand the evolutionary history of the earth and predict the future trend of the earth, while also opening up new living spaces for humans to find potential targets . The ultimate goal of exploring and studying Mars is to serve the sustainable development of the earth and human society.
The Mars exploration mission of "Tianwen 1" is scheduled to complete the three major tasks of "circling, falling, and patrolling" at one time, which also marks the official opening of the Chinese planetary exploration.
Mars exploration data reception is a serious challenge
Li Chunlai pointed out that the distance between the moon and the earth is about 360,000 to 400,000 kilometers, while Mars is 56 to 400 million kilometers from the earth, and the longest distance of the earth fire is about 1000 times the distance between the earth and the moon. Mars exploration is a serious challenge for the data receiving task. The signal from Mars is very attenuated and the signal is very weak. Without the large-caliber antenna, the data receiving task cannot be completed.
In order to realize the data reception of a weak signal from a distance of 400 million kilometers in China ’s first Mars exploration project, the National Astronomical Observatory of the Chinese Academy of Sciences built a 70-meter high-performance receiving antenna (GRAS-4) at Wuqing Station in Tianjin. It is the largest single-caliber under construction in Asia The fully movable antenna is the key equipment to complete the scientific data receiving mission of the Mars rover in China.
"When we are farthest, we may have to add Miyun's 50-meter antenna and 40-meter antenna, and Kunming's 40-meter antenna. Four antennas receive data at the same time, and then perform signal synthesis to complete the reception of Mars exploration data. Mission. "Li Chun said.
Fully equipped with Mars exploration data reception capability in October
Li Chunlai introduced that the newly built 70-meter antenna is a wheel-rail fully movable Cassegrain antenna. The working frequency bands are S, X and Ku. The total weight is about 2700 tons and the height is 72 meters. The main reflection surface has a diameter of 70 meters and consists of 16 The circle consists of 1328 high-precision solid panels, with an area equivalent to 9 basketball courts. It started construction in October 2018 and plans to complete acceptance in 2020.
The completion of the overall lifting of the reflector means that the 70-meter antenna theme structure is basically completed. The remaining 6 circles of peripheral panels will be further laid out, as well as the installation of servo systems, feed networks and refrigeration receivers, and a certain period of time. Only through commissioning, calibration and trial operation can we have the ability to perform tasks.
Li Chunlai said that it is expected that by October 2020, a 70-meter antenna will be fully equipped with data reception capabilities for Mars exploration.
He said that after the completion of China ’s 70-meter antenna, it will become Asia ’s largest single-caliber fully movable antenna, which can greatly improve China ’s ability to receive deep space exploration downlink data, and will complete China ’s first Mars exploration engineering mission and subsequent asteroids and comets. Wait for deep space exploration to lay a solid foundation. (Finish)