SpaceX satellites are making low earth orbit dangerously crowded

Last week a Canadian astronomer at the University of Regina in Saskatchewan did a calculation that made her “want to scream”. Professor Sam Lawler specialises in modelling orbits. Her calculation, prompted by a charred piece of fallen SpaceX junk found on a nearby farm, suggested that SpaceX’s current fleet of Starlink satellites, each travelling at 7 km per second, created an “opportunity for error” every 30 seconds by passing within a kilometre of each other and relying on an automated system to avoid colliding. Last year Starlink reported 25,000 near misses and that number is rising exponentially as the fleet grows from 6,000 satellites to a planned total of 42,000. Since the 70s, spaceflight planners have worried about a critical mass of space junk leading to cascading orbital collisions – a scenario known as the Kessler Syndrome. “SpaceX, please don’t whoopsie us into Kessler Syndrome,” Lawler said on Mastodon. It would, apart from anything, prevent SpaceX getting to Mars.