Astronomers grapple with the impact of huge constellations of satellites

The effects that huge constellations of satellites could have on astronomy are starting to emerge, and astronomers are wondering what this industrialization of space might mean for the future of their field.

The big picture: Companies like SpaceX and Amazon plan to launch thousands of Internet-broadcasting satellites into orbit in the coming years.

Where is it: Satellites can disrupt images taken by powerful telescopes on Earth. In particular, these spacecraft can hamper the ability of scientists to find dangerous asteroids and distant objects of interest.

• Scientists are now suggesting that these satellites should be in relatively low orbits, as this would keep them out of the field of view of large telescopes for much of the night.
• The concerns of the scientific community do not focus solely on streaking satellites in telescope fields of view. Radio astronomers could also face interference from these satellites when transmitting at night.

The plot: Since 2018, SpaceX has launched more than 900 Starlink satellites as part of its constellation, and other companies are rushing to catch up. This rapid pace has not left much time for astronomers to advocate for their needs.

• “We need more ground rules up there, in a rather ‘Wild West’ environment, because more and more people are coming into the game,” said Jeff Hall, of the Lowell Observatory, during a panel at the American Astronomical Society meeting last week.

What to watch: Astronomers are working with space companies to make sure that any interference from their satellites is kept to a minimum.

• The National Science Foundation and the American Astronomical Society have published a joint report on the impact of these satellites on astronomy, and the International Astronomical Union also has a report on the subject.
• SpaceX is working to reduce the visibility of its Starlink satellites in a number of ways, including coating some of them with material to reduce reflectivity.
• A study carried out in December showed that these “DarkSats” are about half as reflective as previous Starlink satellites launched by SpaceX. The company is also experimenting with other methods that could further reduce their reflectivity.