In the race to expand their new broadband-beaming networks in space, two satellites from the fast-growing constellations of rival companies, OneWeb, and SpaceX’s Starlink, came dangerously close to each other in orbit on March 30th, somehow avoiding a collision, representatives from the US Space Force and OneWeb said. It’s the first occurrence of such a collision-avoidance event for the two rival companies.
Just five days after OneWeb launched its latest batch of 36 satellites from Russia, “red alerts” from the US Space Force’s 18th Space Control Squadron were received by the company, warning of a possible collision with a Starlink satellite. Because OneWeb’s constellation operates in higher orbits around Earth compared to Low Earth Orbit (LEO) Starlink satellites, the company’s satellites must pass through SpaceX’s mesh of Starlink satellites.
A 1.3 percent collision probability alert was indicated by the Space Force, with the two satellites coming as close as 190 feet — a dangerously close proximity for satellites in orbit. Unimaginable calamities can occur if satellites collide in orbit, a cascading disaster that could generate debris and send them on crash courses with other satellites nearby.
Currently, a lack of national or global authority that would force satellite operators to take action on predicted collisions is causing an issue. Space Force’s urgent alerts sent OneWeb engineers into a frenzy. They emailed SpaceX’s Starlink team to coordinate maneuvers and send the two satellites at safer distances from one another.
“COORDINATION IS THE ISSUE. IT IS NOT SUFFICIENT TO SAY ‘I’VE GOT AN AUTOMATED SYSTEM.’”
According to OneWeb’s government affairs chief Chris McLaughlin, SpaceX disabled its automated AI-powered collision avoidance system to allow OneWeb to steer its satellite out of the way while coordinating with OneWeb. This automated system has sparked controversy, raising concerns from other satellite operators who say that it gets difficult to coordinate and know which way the system will move a Starlink satellite in the event of a close approach. “Coordination is the issue,” McLaughlin says. “It is not sufficient to say ‘I’ve got an automated system,’ because the other guy may not have, and won’t understand what yours is trying to do.”
Elon Musk’s SpaceX has roughly 1,370 Starlink satellites in orbit out of an estimated 12,000-satellite network of global broadband coverage. OneWeb has launched 146 satellites so far, operating in higher orbits around Earth, of the roughly 650 it plans to send into orbit for a similar global network. Amazon has pledged to join the same race, with plans of sending over 3,000 satellites in LEO.
“This event was a good example of how satellite operators can be responsible given the constraints of global best practices,” says Diana McKissock, the head of the Space Force 18th Space Control Squadron’s data sharing and spaceflight safety wing, according to The Verge. “They shared their data with each other, they got in contact with each other, and I think in absence of any global regulation, that’s… the art of the possible.”
“WHAT IS THE POINT OF HAVING IT IF YOU HAVE TO TURN IT OFF WHEN THERE’S GOING TO BE A POTENTIAL COLLISION?”
McKissock has given SpaceX credits where it’s due as the aerospace manufacturer has made efforts to increase its transparency in orbit; the company currently provides location data of its satellites to other operators. But for avoiding collisions, its automated system is a closed book. Openness and coordination are of the utmost need here, analysts and operators say.
“What is the point of having it if you have to turn it off when there’s going to be a potential collision?” Victoria Samson of the Secure World Foundation says, adding that who would be held responsible if a collision actually occurred is still a mystery owing to the lack of an international framework.
Satellite maneuvers in space are common, but worry in the industry is mounting as top companies race to toss more satellites into space. And this Starlink close call isn’t the first, a European Space Agency (ESA) satellite had to move out of the way of a Starlink satellite, in 2019, to avoid a potential collision. SpaceX said at that time that it didn’t move its satellite because of a computer bug that prevented proper communication with ESA.
“IT’S JUST CROSSING YOUR FINGERS”
“OneWeb and others will have to transit through Starlink to reach their destinations, so SpaceX needs to ensure now that other satellite operators can do that safely,” says Caleb Henry, a satellite industry analyst at Quilty Analytics.
McKissock says the 18th Space Control Squadron is fully aware of the industry concerns with SpaceX’s autonomous avoidance approach. “So it’s been interesting,” she says. “But like I said, I’m glad they talked to each other. The scary situation is when one of the operators is not communicative, and then it’s just crossing your fingers.”