By Kim Rathcke Jensen, AAU Communication and Public Affairs
Photo: Colourbox

Space is becoming overcrowded with satellites, an expert warns. By 2040, there could be as many as half a million satellites in orbit around Earth. That increases the risk of collisions.

There is a traffic jam building up in space. At least in the atmosphere around Earth, which is on its way to becoming filled with satellites.

Now, the head of the Space Tech Center at Aalborg University, Israel Leyva Mayorga, is questioning whether there is room for more.

“There is always a risk of collisions. But that risk is going to increase significantly in the coming years,” says Associate Professor Israel Leyva Mayorga.

“Today, satellites are critical infrastructure for our modern society on Earth. So failures can have consequences for climate monitoring, weather forecasting, navigation, disaster warning, and everything else we use satellites for,” says Israel Leyva Mayorga.

The first satellite was launched in 1957, when it orbited alone for a few months before burning up in the atmosphere. Since then, humanity has sent tons of satellites into space. Today, there are approximately 14,000 active satellites in orbit around Earth.

SpaceX alone plans to launch 42,000 satellites. China is planning three constellations of 38,000 satellites. In total, applications for the launch of one million satellites have been submitted to the UN’s International Telecommunication Union.

“The number of applications is usually higher than the actual number that ends up being launched. So it is difficult to make a precise estimate. But there is no doubt that significantly more satellites are on the way, and that the risk of collisions is increasing,” says Israel Leyva Mayorga.

NASA’s Ames Research Center estimates that by 2040 there could be as many as 560,000 satellites in orbit around Earth. And that all of them will be in the most heavily trafficked orbits around Earth, in low Earth orbit from approximately 500–2,000 kilometres.

That is problematic, says Israel Leyva Mayorga.

Space debris creates more space debris

Israel Leyva Mayorga has made a rough calculation showing that, in theory, there is room for approximately 260,000 satellites around Earth, if they are organised so that they are spaced 200 km apart.

“But that does not include launch and deorbiting, where the risk of collisions is highest. So the real number should be much lower and closer to 100,000,” says Israel Leyva Mayorga.

The greatest risk is the so-called Kessler effect. If, for example, two satellites collide, it creates a large number of fragments, which can then collide with other satellites and in that way start a chain reaction.

“That is why it is necessary to find new ways of designing satellite constellations, so that we have the smallest possible number of satellites. We need to plan better and develop business models like the ones we know today from mobile networks, where different operators and service providers can use the same network. And we need to plan the launch and deorbiting of old satellites using more sustainable approaches,” says Israel Leyva Mayorga.

That number is set to rise dramatically by 2040.

SpaceX alone plans to launch 42,000 satellites. China is planning three constellations of 38,000 satellites. In total, applications for the launch of one million satellites have been submitted to the UN’s International Telecommunication Union.

“The number of applications is usually higher than the actual number that ends up being launched. So it is difficult to make a precise estimate. But there is no doubt that significantly more satellites are on the way, and that the risk of collisions is increasing,” says Israel Leyva Mayorga.

NASA’s Ames Research Center estimates that by 2040 there could be as many as 560,000 satellites in orbit around Earth. And that all of them will be in the most heavily trafficked orbits around Earth, in low Earth orbit from approximately 500–2,000 kilometres.

That is problematic, says Israel Leyva Mayorga.

Space debris creates more space debris

Israel Leyva Mayorga has made a rough calculation showing that, in theory, there is room for approximately 260,000 satellites around Earth, if they are organised so that they are spaced 200 km apart.

“But that does not include launch and deorbiting, where the risk of collisions is highest. So the real number should be much lower and closer to 100,000,” says Israel Leyva Mayorga.

The greatest risk is the so-called Kessler effect. If, for example, two satellites collide, it creates a large number of fragments, which can then collide with other satellites and in that way start a chain reaction.

“That is why it is necessary to find new ways of designing satellite constellations, so that we have the smallest possible number of satellites. We need to plan better and develop business models like the ones we know today from mobile networks, where different operators and service providers can use the same network. And we need to plan the launch and deorbiting of old satellites using more sustainable approaches,” says Israel Leyva Mayorga.