Shijian-21 succeeded in its first orbital cleaning mission… and in what way! The Chinese satellite was launched on October 24, 2020, under the rather suspicious eye of the Americans who feared to be dealing with a military device. These suspicions were however largely unfounded: at the end of December, Shijian-21 approached the inactive satellite Beidou-2 G2 (also of Chinese origin), docked with it and on January 22 would have moved it to another orbit located 3000 kilometers above the geosynchronous orbit. Beidou-2 G2 no longer poses any particular risk to other satellites in geosynchronous orbit.
For specialists, there is no doubt that China has just achieved a real technological feat: so far, the movements of inactive satellites have not exceeded 300 km above their initial position. The feat is all the more remarkable as the operation would have encountered no hitch. After clearing the area of bulky debris, Shijan-21 returned to geosynchronous orbit.
It should be noted that China is not the first nation to send a cleaning satellite into space: the company Space Logistics (subsidiary of the American Northrop Grumman) launched satellites of the same type at the beginning of last year. The MEV 2 tug satellite (Mission Extension Vehicle) had thus docked with the active satellite IS-10-02 from Intelsat at an altitude of 36,000 km (geostationary orbit).