We could see as many satellites as stars in our sky by 2030 thanks to space junk, astronomers warn
Within a decade, we could be seeing as many satellites as stars in our night sky, thanks to all the "space junk" that is being launched into the Earth's orbit, astronomers have warned.
Pre-2019, there were about 2,000 satellites orbiting the Earth. The number today is double that. And in 10 years, that number could shoot up to 100,000, according to Andy Lawrence, regius professor for astronomy at the University of Edinburgh.
If that happens, stargazers could be seeing as many as 10 satellites in their field of view every time they look out the night sky, he said.
But it is not just about the aesthetics of our sky. Overcrowding the Earth's orbit with satellites could be dangerous, Prof Lawrence said, leading to more crashes between space objects. The break-up of objects could in turn produce more space debris.
Even the tiniest speck could cause noticeable damage to satellites, as they travel very fast in space.
Prof Lawrence - author of the book Losing the Sky - estimates there could be "a couple million pieces of junk" so small that telescopes cannot see them from Earth.
Space junk is defined as any object in space that has been put up there by humans. It doesn't just encompass satellites, but also includes modules that get left behind as rockets and satellites are launched into space - although a lot of that does get burnt up in the atmosphere.
Astronomer Royal for Scotland Catherine Heymans has likened the problem of space debris to pollution: "We're really really polluting this space around our very precious planet.
"So not only are we polluting our rivers, our oceans, our seas, forests, we're also now starting to pollute the orbit around Earth."
She added: "Space is one of the last wildernesses that we have."
The Edinburgh University astrophysics professor continued: "If you remember the New England song where they say: 'I wished on two shooting stars last night, but they were only satellites' - that's going to be us.
"We're not going to be able to distinguish stars from satellites and that seems so wrong given that humanity has relied on the stars to navigate, to show us our place in our universe."
Prof Lawrence first became aware of the issue of space junk after spotting streaks on his wide-field pictures of the night sky in late 2019.
He said: "It really took us by surprise. Suddenly, there were streaks across our pictures and then I found that amateur astronomy stargazers were having the same problem.
"And that turned out to be this new project by Elon Musk, Starlink, to launch thousands of satellites to try and give people fast internet connections."
He soon realised the problem was not just confined to streaks in his pictures.
He said: "We rely on space for a lot of things: monitoring the weather, communications, even the military have their space satellites.
"If space becomes a more dangerous place to be, those things will be at risk."
He continued: "One day, if a major football game gets shut down and you can't see it on your TV because something has crashed into the satellite that's beaming the signal, people are going to be cross then."
While both Prof Heymans and Prof Lawrence acknowledged the benefits of the internet and helping the world stay connected, they say space companies are going about it the wrong way.
They explained that the satellites put up by Elon Musk are low orbit satellites, which appear to be designed for faster connections, rather than broader internet coverage.
Satellites further away can beam signals down to a lot of people in one go, Prof Lawrence explained, but it will take longer for signals to travel up to the satellite and back down to Earth.
"It's not worth throwing away our gorgeous night sky" to get ultra fast internet, Prof Heymans said.
Prof Lawrence and Prof Heymans are among a group of astronomers who held a live virtual discussion on space junk on Tuesday.