"Tianwen No.1" will advance towards Mars

Why China's planetary exploration first explored Mars

　　On the fifth China Space Day on April 24, the high-profile China's first Mars exploration mission was announced: "Tianwen-1". As soon as the news came out, China's Mars exploration mission once again triggered a wave of attention.

　　On April 25, the Mars mission made new progress: 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 same day.

　　"After the project is completed, it will become the largest single-caliber fully movable antenna in Asia and a key device for completing the scientific data reception mission of the Mars rover." China's first Mars exploration project deputy chief designer and chief commander of the ground application system, Chinese Academy of Sciences Li Chunlai, deputy director of the National Astronomical Observatory, said in an interview with reporters on April 26.

So why did Chinese planetary exploration first explore Mars?

　　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 celestial body." Li Chun said that China's first independent exploration of Mars is not only to explore the existence and evolution of Mars life, but also to understand the evolution history of the earth Predict the future changing trend of the earth, and at the same time open up new living spaces for human beings to find potential targets. In his view, the ultimate goal of detecting and studying Mars is to serve the sustainable development of the earth and human society.

　　Li Chun said that according to the plan, the Martian exploration mission of "Tianwen No. 1" must complete the three major tasks of "circling, landing, and patrolling" at one time.

What is the difference between Mars exploration and Moon exploration?

　　Li Chun said that the longest distance of the earth fire is about 1000 times the distance of the earth and the moon, which will bring a series of problems.

　　Aerospace expert Pang Zhihao said that the longer the distance, the weaker the signal, and the ground fire distance will also bring a signal delay of at least 10 minutes. The critical time for the probe to enter Mars orbit and landing can only be relied on by researchers to input data in advance, and the probe can make independent judgments, which is equivalent to "blind landing".

　　According to Li Chunlai, the newly built GRAS-4 antenna has a total weight of about 2700 tons, a main reflecting surface with a diameter of 70 meters, and an area equivalent to the size of 9 basketball courts. The technology adopted by the antenna can improve antenna efficiency, reduce system noise, and improve anti-interference ability. The antenna started construction in October 2018 and is scheduled for completion and acceptance in 2020. Today, the complete lifting of the reflector is completed, which means that the main structure of the 70-meter antenna is basically completed. "It is estimated that by October 2020, a 70-meter antenna will be fully equipped with data reception capabilities for Mars exploration." Li Chun said that the antenna will lay the foundation for the completion of China's first Mars exploration engineering mission and subsequent deep space exploration such as asteroids and comets. .

　　According to the plan, China will implement the first Mars exploration mission in 2020. The goal is to achieve Mars orbit and landing patrols through one launch mission, conduct global and comprehensive exploration of Mars, and conduct patrol surveys on key areas on Mars.

　　According to previous news from China Aerospace Science and Technology Corporation, China ’s first Mars exploration is expected to be implemented in July this year, and it will be launched by the Long March 5 Yao-4 rocket at the Wenchang launch site in Hainan.

　　Newspaper Beijing, April 26th

　　China Youth Daily · China Youth Daily reporter Qiu Chenhui Source: China Youth Daily