The reporter learned from the China National Space Administration that the Queqiao-2 relay satellite has completed the in-orbit communication test. After evaluation, the relay satellite platform and payload are working normally, and the functions and performance meet the mission requirements, which can provide relay communication services for the fourth phase of the lunar exploration project and the subsequent lunar exploration missions at home and abroad, and the mission has been a complete success.
On March 20, 2024, the Long March-8 launch vehicle satellite mount camera took images. The Queqiao-2 relay satellite was successfully separated from the launch vehicle, the solar wing and the parachute antenna were successfully deployed, and the Tiandu test satellite was displayed on the left side of the image.
After its launch on March 20, the Queqiao-2 relay satellite entered the 24-hour circumlunar elliptical mission orbit on April 2 as planned after mid-course correction, near-moon braking, and circumlunar orbit maneuvering. On April 6, the Queqiao-2 relay satellite successfully completed the communication test with Chang'e-4, which is carrying out a mission on the far side of the moon. From April 8th to 9th, the Queqiao-2 relay satellite and the Chang'e-6 probe (ground state) carried out a communication test.
The Tiandu-1 and Tiandu-2 communication technology test satellites, which were launched simultaneously, entered the orbit of the circumlunar mission on March 29, and successfully implemented the separation of the two satellites on April 3, and a series of communication technology verification is being carried out.
On April 8, 2024, Tiandu-2 took images. Lunar imaging data in the far-infrared spectral segment with a wavelength of 8~14um, and the smaller celestial body in the background is the Earth.
The Queqiao-2 relay satellite and the Tiandu test satellite adopt a large elliptical frozen orbit around the moon as their mission orbits. Due to the irregular shape and structure of the moon, spacecraft flying close to the moon are affected by the gravitational pull of the moon, and the flight trajectory is prone to deviation. The circumlunar large elliptical frozen orbit is a circumlunar orbit in a stable state, in which the spacecraft flies, which is able to minimize the deviation of the flight trajectory.
The choice of the large elliptical frozen orbit around the moon as the mission orbit of Queqiao-2 has many advantages. The first is to increase the communication rate, compared with Queqiao, the mission orbit of Queqiao-2 is closer to the moon, and the communication rate of data transmission will be greatly improved. Compared with the Queqiao orbiting around the Earth-Moon Lagrange L2 point, the visibility of the Quebridge-2 in the orbit of the lunar large ellipse mission to the south pole of the moon has been significantly improved, and the communication coverage of the south pole of the moon has been greatly improved. The third is to save satellite fuel, and Queqiao-2 can maintain a long-term stay in this orbit with very little fuel.
Subsequently, the Queqiao-2 relay satellite will provide relay communication services for Chang'e-4 and the Chang'e-6 mission to be launched as planned, and carry out corresponding scientific exploration at the right time.
Source: People's Daily client Feng Hua Wang Hao