The number of satellites in orbit is growing at an accelerated pace, which is causing concern in the scientific community. In a series of articles in Nature scientists warn of an unprecedented global threat to nature and science from satellites. Light pollution will have material and cultural consequences, many of which are difficult to predict but should be expected.
According to the most conservative estimates, since 2019 the number of satellites at an altitude of up to 2 thousand km has doubled, thanks primarily to SpaceX’s Starlink constellation, designed to deliver satellite Internet. If all announced plans are implemented, thousands more satellites will be added to them in the near future.
Each new satellite increases the risk of colliding with another object in Earth’s orbit and creating lots of debris. This will increase the already impressive cloud of debris in orbit and therefore multiply the fluxes of light reflected back to Earth.
Probably the first to suffer from light pollution are astronomers and all those who serve this industry. A specially conducted simulation with the Vera Rubin observatory under construction in Chile with an unprecedented resolution matrix showed that the darkest part of the sky will become brighter by 7.5% by the end of the next decade.
Approximately this many stars the observatory will not see and will also miss a number of phenomena that can be valuable to science. It will be especially disappointing if the observatory’s widest array misses an Earth-threatening asteroid. In this light, the claim of a global threat from satellites ceases to be unwarranted hysteria.
In material terms, illumination from satellites will lead to an increase in observation time and direct cost overruns. For the Vera Ruby Observatory, that means an extra year of observing and an extra $21.8 million in the budget.
But the situation could be worse, say the authors of another paper. According to them, the harm of lighting up the night sky and the consequences of it are very, very underestimated. Everything will be much worse, and until the end it is not clear how much.
The problem also has a cultural aspect. Renowned astronomer Aparna Venkatesan of the University of San Francisco says satellites threaten “our ancient connection to the night sky.” “Space is our common heritage and an ancestor that connects us through science, storytelling, art, origin stories, and cultural traditions, and now it is under threat,” she wrote in a commentary to an article in Nature.
The scientists are aware that “it is naïve to hope that the rapidly developing space economy will self-limit if it is not forced to do so,” given the economic interests at stake. They insist that the problem be approached with full attention before it is too late. This is not the first such appeal, and apparently it will not be the last. Another question is whether it will be heard by the responsible factors.