At 5:28 PM on the 21st, the Chang'e 4 relay satellite, the “Yanqiao”, was launched to provide relay communication services for the Chang’e No. 4 lunar lander and lander that was launched at the end of this year. In addition, “Yanqiao” also carried laser angle reflections. , will carry out ground-based laser ranging test, undertake the lead research work of 'Tianqin Plan'.
It is understood that, after entering the mission track, 'Yaoqiao' will try to carry out the laser distance test in the history of human beings. The laser distance test is a scientific measurement of the distance between the laser and the satellite. Its principle is to transmit highly isotropic pulses. The laser beam is directed at an angle mirror placed on the surface of the satellite. The distance between the satellite and the satellite is calculated by sending and receiving the time difference. At present, the longest distance laser ranging test in human history is the moon laser ranging. In 1969, Apollo 11 was An array of laser distance measuring mirrors was placed on the Moon. Since then, the United States, France, Japan, and China have completed the test. There are not many countries that have mastered this technology. After all, they wanted to find and locate on the moon's surface 380,000 kilometers away. Aiming at small laser mirrors is difficult as finding a needle in a haystack. If the "Yaoqiao" satellite laser ranging test is successful, it will be a great leap in the measurement technology of spacecraft.
It is reported that Luo Jun academician of Huazhong University of Science and Technology began to lay out the laser angle reflector in 2015. This device equipped by 'Yanqiao' will do pioneering research for the future 'Space Music Project' to detect gravitational waves in space.
According to reports, the project will realize the first time in the world that the pure reflective laser ranging over the Earth-Moon distance is the first step in the 'Tian Qin Project' implementation roadmap '0123 Plan', which is part of the '0' plan. The purpose is to develop lunar and deep-space satellite laser ranging technology to provide technical verification and reserves for the precision orbit determination of the late 'Tianqin' satellites.
Source: Science and Technology Daily
