On 3 Dec 2021, The Permanent Mission of China sent a note to UN General Assembly complaining two dangerous approaches to China's Shenzhou space station from SpaceX's Starlink satellites during 2021.
These two dangerous approaches were happening in July and October respectively and they almost caused collisions of the Starlink satellites and the Shenzhou space station because the two SpaceX satellites manoeuvred continuously to the orbit of China's space station. These dangerous approaches forced the China's space station to do evasive manoeuvre to avoid collisions.
According to the note, below were what happened exactly:
1. The first collision avoidance
As from 19 April 2020, the Starlink-1095 satellite had been travelling stably in orbit at an average altitude of around 555 km. Between 16 May and 24 June 2021, the Starlink-1095 satellite manoeuvred continuously to an orbit of around 382 km, and then stayed in that orbit. A close encounter occurred between the Starlink-1095 satellite and the China Space Station on 1 July 2021. For safety reasons, the China Space Station took the initiative to conduct an evasive manoeuvre in the evening of that day to avoid a potential collision between the two spacecraft.
2. The second collision avoidance
On 21 October 2021, the Starlink-2305 satellite had a subsequent close encounter with the China Space Station. As the satellite was continuously manoeuvring, the manoeuvre strategy was unknown and orbital errors were hard to be assessed, there was thus a collision risk between the Starlink-2305 satellite and the China Space Station. To ensure the safety and lives of in-orbit astronauts, the China Space Station performed an evasive manoeuvre again on the same day to avoid a potential collision between the two spacecraft.
From what have been mentioned, it looks like there might be some unknown issues to SpaceX's Starlink satellites and there is no comment from SpaceX yet on this matter.
However this poses potential risk to other satellites on different orbits as there are so many such small satellites on the orbit not only from Starlink but also from other similar systems in the world. If they are not well controlled and collisions happen, it would cause problems as those debris are more challenging to track and clean up. Hence the information to all the involved parties who are utilizing the space is to be more responsible.
