SpaceX has signed an agreement with the US National Science Foundation (NSF) that promises to help prevent its Starlink satellite internet system from interfering with the field of astronomy.
The Starlink network currently includes 3,300+ orbiting satellites, which can reflect sunlight and interfere with astronomical observations and photo-bomb images of the night sky. So for months now, SpaceX has been in talks with scientists on minimizing Starlink’s impact on astronomy. The FCC also made it a requirement for SpaceX to reach an agreement with the NSF as a condition for approving a second-generation Starlink network.
The agreement says both SpaceX and the NSF will work together to reduce the brightness of satellites through physical design changes, their orientation in orbit, and other methods. Back in July, SpaceX debuted some of the design improvements, which include using new materials and colors on the satellites to cut down on the reflections.
Under the agreement, observatories won't have to turn off their laser guides when Starlink satellites approach overhead. “Therefore, adaptive optics lasers at ground-based facilities will no longer undergo multiple closures every time the SpaceX satellites pass nearby,” the NSF says.
SpaceX will also coordinate to prevent Starlink satellites from beaming communications during observations at key radio astronomy facilities. In addition, Starlink committed to working with the NSF “as interference arises or new challenges” emerge from the growing Starlink network.
“We are setting the stage for a successful partnership between commercial and public endeavors that allows important science research to flourish alongside satellite communication,” NSF Director Sethuraman Panchanathan said in the announcement.
The news represents a win for the astronomy community. However, the agreement only covers Starlink—not satellite internet networks from other companies. In November, the International Astronomical Union expressed concerns about the BlueWalker 3 test satellite from Texas-based AST SpaceMobile. The satellite’s communication array is so large it’s “now one of the brightest objects in the night sky, outshining all but the brightest stars,” the union said.
BlueWalker 3 is also sparking worries it’ll disrupt observations from radio-based telescopes. In response, AST SpaceMobile said: "We are eager to use the newest technologies and strategies to mitigate possible impacts to astronomy.” The company also plans on avoiding beaming signals from BlueWalker 3 and future satellites to radio-based observatories.
Like SpaceX, rival companies including AST SpaceMobile and Amazon have plans to operate large fleets of communication satellites in Earth’s orbit. This has stirred up worries that next-generation satellite networks will create light pollution. Hence, some astronomers and environmental groups argue the upcoming satellite constellations pose a threat to the night skies. As a result, the International Dark-Sky Association, along with Dish Network, has sued to stop SpaceX from launching its second-gen Starlink satellites into orbit.