Starlink's 'megaconstellation' of 12,000 satellites could account for 90% of near misses in orbit, scientist predicts

• Starlink satellites will ultimately be responsible for 90% of near misses in Earth orbit, a scientist predicts.
• Hugh Lewis told Space.com that Starlink satellites were already involved in about 50% of near misses.
• Near misses occur when two spacecraft pass within 1 kilometer (0.6 miles) of each other.

Starlink satellites will ultimately be involved in 9 in 10 near misses between spacecraft that are orbiting Earth, a scientist and space debris expert has predicted.

Once the "megaconstellation" of Starlink satellites has reached its intended size of 12,000, it will be responsible for 90% of these close encounters, research by Hugh Lewis, of the University of Southampton, published by Space.com, suggests.

Starlink, which is owned by Elon Musk's SpaceX, aims to create "the world's most advanced broadband internet system." It has already launched around 1,700 satellites into Earth orbit, which are responsible for about half of all near misses presently, Professor Lewis' research suggests.

Near misses in Earth orbit occur when two spacecraft pass within 1 kilometer (0.6 miles) of each other. With a rapidly growing number of satellites being sent into orbit, scientists are concerned about the increased likelihood of collisions, and the potential for a chain reaction that leads to multiple collisions.

Lewis examined data from the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (Socrates) database, which tracks satellite orbits and models their trajectory to assess collision risk. He looked at data back to May 2019, when Starlink launched its first batch of satellites.

Lewis said that Starlink satellites were responsible for 1,600 close encounters between two spacecraft a week. Excluding near misses involving two Starlink satellites, the figure was 500, he said.

He told Space.com that the number of encounters picked up by the Socrates database "has more than doubled and now we are in a situation where Starlink accounts for half of all encounters."

OneWeb, a Starlink competitor, has 250 satellites in orbit, which are involved in 80 near misses with other operators' satellites each week, according to data that Lewis provided to Space.com.