SpaceX Describes Efforts to Minimize Adverse Effects of Starlink Satellites on Astronomy

On Monday, 27 April, the Astro2020 Decadal Survey Committee held a virtual meeting on the topic "Optical Interference from Satellite Constellations." Among those who made presentations were Joel Parriott, AAS Deputy Executive Officer & Director of Public Policy; Patrick Seitzer (University of Michigan), a member of the AAS Committee on Light Pollution, Radio Interference, and Space Debris; Tony Tyson (University of California, Davis), Chief Scientist of the Vera C. Rubin Observatory (Large Synoptic Survey Telescope); and founder Elon Musk and other representatives of SpaceX, the company behind the Falcon and Starship rockets, Dragon and Crew Dragon spacecraft, and the ever-growing Starlink constellation of communication satellites.

Download the Presentations (PDFs)

SpaceX subsequently posted a rather lengthy and detailed update on its efforts to mitigate the adverse effects of its Starlink satellites on ground-based astronomy. It begins, "SpaceX is launching Starlink to provide high-speed, low-latency broadband connectivity across the globe, including to locations where internet has traditionally been too expensive, unreliable, or entirely unavailable. We also firmly believe in the importance of a natural night sky for all of us to enjoy, which is why we have been working with leading astronomers around the world to better understand the specifics of their observations and engineering changes we can make to reduce satellite brightness."

The article describes two of the company's goals:

• Making the satellites generally invisible to the naked eye within a week of launch.
• Minimizing Starlink's impact on astronomy by darkening satellites so they do not saturate observatory detectors.

It then goes on to provide much more information than has been publicly disclosed before about the satellites' orbits and flight configurations and the steps the company is taking to reduce their brightness, including darkening some parts of the satellites and shielding others from direct sunlight.

Read the SpaceX Starlink Discussion

As SpaceX explains, "The Vera C. Rubin Observatory [is] the most difficult case to solve...due to its enormous aperture and wide field of view... so we've spent the last few months working very closely with a technical team there to do just that.”

“I'm cautiously optimistic,” says Tyson, “but it will be months before we can validate joint solutions to mitigating many of the effects of even the darkened Starlinks on the Rubin Observatory’s wide-field survey data.”

Tyson adds that he was pleased to hear Elon Musk personally acknowledge the urgency of minimizing Starlink’s interference with observational astronomy. “And SpaceX’s new online article sets a high standard for all operators of low-Earth-orbit satellites to follow.”