Experts warn that the excessively bright Chinese satellites Qianfan could negatively impact astronomical activities and many other issues.
According to LiveScience on October 15, astronomers have analyzed ground observations of Chinese satellites and found that they are much brighter than expected.
For instance, the Qianfan satellites (meaning “thousand sails”), launched in August, have been observed to be bright enough to be seen with the naked eye at night.
China launches Qianfan satellites from Taiyuan Satellite Launch Center on August 6 – (Photo: CNSA).
Qianfan is a “super constellation” of communication satellites produced by the state-owned Chinese company Shanghai Spacecom Satellites Technology. This satellite network is Beijing’s response to SpaceX’s Starlink satellite project, which is designed to provide high-speed global internet.
There is not much information about the project or design of the Qianfan satellites, but Chinese state media have previously revealed that Beijing plans to launch up to 15,000 Qianfan satellites into space by 2030, according to Reuters.
The first batch of Qianfan satellites was launched on August 6 aboard a Long March 6A rocket. This mission successfully deployed 18 satellites into low Earth orbit (LEO), but the second stage of the rocket broke into over 300 pieces, posing a danger in LEO.
Scientists also warn that some Qianfan satellites are scheduled to be deployed at altitudes lower than LEO, meaning they could be 1 to 2 degrees brighter than the recently observed Qianfan satellites.
Once this massive satellite constellation is formed, it “will negatively impact both professional and amateur astronomical activities unless operators reduce their brightness”, the analysis team stated.
The team noted that the amount of reflected light from communication satellites could be reduced by using integrated mirrors, similar to what SpaceX has done with its second generation of Starlink satellites launched last year. They also urged China to take similar measures.
In addition to causing light pollution in the night sky, communication satellites can also disrupt radio astronomy by leaking radiation into space. This is currently an issue with the latest generation of Starlink satellites. However, further observations are needed to determine if Qianfan satellites exhibit similar problems.
Moreover, satellite constellations have been criticized for increasing the risk of collisions between spacecraft in LEO, creating space debris, and polluting the atmosphere when they burn up during re-entry to Earth.
