...Blurry streaks of light created by fast-moving artificial satellites are already known to mar images taken by ground-based observatories. Today, researchers report in Nature that space-based telescopes will not escape such interference as fleets of private satellites proliferate. The researchers found that in the next decade, satellite trails could taint roughly 96% of the images taken by some space-based telescopes, and a single image could contain as many as 92 streaks...

The researchers simulated roughly 18 months of observations, taking faux space pictures with various numbers of satellites in orbit ...They found that if 560,000 satellites are in orbit — the number currently planned for launch — their trails will contaminate from 40% to more than 96% of each telescope’s images. And with one million satellites in orbit, the number of streaks per image reaches 165 for some observatories. At that rate, “we will have fewer discoveries, less interesting images and, in general, less knowledge”, says Borlaff. SpaceX did not respond to a request for comment about the effects of its constellation...

This Nature report is paywalled, but you can read enough of it for free to get the essentials