Swarms of cheap “CubeSats” are currently being planned by companies who want to bring wireless internet access to every corner of the globe. But there’s nothing to stop these sprawling “megaconstellations”, which would include thousands of spacecraft, from colliding with other satellites and unleashing hazardous space debris in low Earth orbit.
Hugh Lewis at the University of Southampton in the UK has sounded the alarm about the risk of small satellite collision cascades before. That was in 2014, when 100 or so CubeSats were being launched per year.
Since then, a number of space-flight firms have announced plans to beam internet services around the globe from vast numbers of satellites, which would be known as megaconstellations. There are only 1300 working satellites in orbit now. But OneWeb, which hopes to launch in 2018, will need 648 satellites, Boeing plans a 2900-satellite fleet, and Samsung and SpaceX both plan 4000-strong swarms.
Now, Lewis and his colleagues have used a supercomputer to simulate 200 years of possible orbits for 300 different megaconstellation scenarios. Their results, revealed this week at a European Space Agency conference on space debris in Darmstadt, Germany, suggest a raft of new rules need hammering out to reduce debris risks.
The supercomputer revealed that megaconstellations boost the risks of a catastrophic collision – in which a satellite is completely destroyed – by 50 per cent.