It’s been three years since SpaceX, an aerospace company in Hawthorne, California, launched its first batch of Starlink Internet-communication satellites, sparking concern among astronomers about the streaks the satellites leave in photographs of the night sky. Since then, many other Starlinks have launched: more than 2,300 of them now orbit Earth, comprising nearly half of all operational satellites.

Scientists have made some progress in coping with the onslaught. For instance, within days the International Astronomical Union (IAU) will debut a website including tools to help telescope operators predict satellite locations so that they can point their instruments elsewhere1.

But accumulating evidence reveals just how much these satellite ‘megaconstellations’ will interfere with astronomical observatories and other skywatchers around the globe. And satellite companies have not yet found a solution. SpaceX had been trying to address the problem by putting sun-blocking shades on its Starlinks to dim their appearance in the night sky. But Nature has learnt that the company has stopped doing so.

Tens of thousands of new satellites could be launched in the next few years. “This is an unsustainable trajectory,” says Meredith Rawls, an astronomer at the University of Washington in Seattle. “At the moment, our science is fine. But at what point will we miss a discovery?”

To read more, click here.