Elon Musk rejects claims that its satellites are pulling rivals out of space

Elon Musk dismissed criticisms that his SpaceX company’s Starlink satellites were taking up too much space and said there could be room for “tens of billions” of spacecraft in low Earth orbit.

“The space is extremely huge, and the satellites are very small,” Musk said. “This is not a situation where we are effectively blocking others in any way. We don’t stop anyone from doing anything, nor do we intend to.”

His comments, made in an interview with the Financial Times, were in response to an assertion by Josef Aschbacher, director of the European Space Agency, that Musk is “set the rules” for the new commercial space economy. Speaking to the FT earlier this month, Aschbacher warned that Musk’s rush to launch thousands of communications satellites will leave fewer radio frequencies and orbital windows available to others.

SpaceX, Musk’s private space company, has launched nearly 2,000 satellites from its Starlink broadband communications network and has plans for tens of thousands more.

Rejecting suggestions that he was “squeezing” future competitors into satellites, Musk compared the number of low-Earth orbiting satellites to what he said are two billion cars and trucks on the planet. Each orbital “shell” around the Earth is larger than the planet’s surface, he said, with an additional shell every 10 meters further into space.

“That would mean space for tens of billions of satellites,” he said. “A few thousand satellites are nothing. It’s like a few thousand cars on Earth—​they’re nothing.”

Some experts have challenged Musk’s claims that low-Earth orbiting satellites can safely match the density of cars and trucks on the Earth’s surface.

Spacecraft traveling at 27,000 km/h need much more spacing than cars to adjust their orbits to avoid collisions, said Jonathan McDowell, an astrophysicist at the Smithsonian Astrophysics Center at Harvard. At that speed, a three-second gap would only leave room for about 1,000 satellites in each orbital shell, he calculated.

Potential collisions can only be identified when they are close to occurring, because of the difficulty of calculating the trajectories of many different satellites, and because changes in solar climate affect their trajectories, McDowell said.

“For many space users, planning a maneuver to avoid accidents takes hours or days, and that suggests that space is already overcrowded,” he said.

China complained this month that two Starlink satellites forced the Chinese space station to take “preemptive collision avoidance control” measures in October and July to “ensure the safety and life of astronauts in orbit.”

Laura Forczyk, a space analyst at the space consulting group Astralytical, said Musk’s comparison of satellites to land vehicles was “flight” but added: “He’s basically right it’s a traffic management problem.”

The rush to launch new communications networks with thousands of satellites had revealed a clear need for greater coordination among countries to decide “how orbital space will be distributed and space traffic managed,” she said.

For Forczyk, Aschbacher’s criticisms of Starlink were “based on emotion, not facts.”
“I have to wonder if similar complaints were made when certain airlines started putting more planes on defined routes. No one owns the sky, and everyone is free to use it,” he said.

Translated by Luiz Roberto M. Gonçalves