Space Congestion: What is crowding Earth's orbit? How is it a threat?

It was in 1978 that NASA scientist Donald Kessler warned of a potential catastrophic chain of reactions that could turn Space into an extra-territorial junkyard. The theory known today as Kessler’s Syndrome posited that one day, the space around Earth would become so crowded with active objects and detritus of past space missions that it would be extremely tough, if not impossible, for mankind to launch new satellites. It has been over 50 years since humans made their first leap in the direction of space launches and as it turns out, Kessler’s Syndrome seems far from being just a theory.

Space is vast. How is it getting congested?

On October 4, 1957, Soviet Union launched the first artificial object into space-artificial Earth Satellite Sputnik 1. Since then, hundreds of thousands of rockets, satellites, spacecrafts, and other space objects have been thrust into the same trajectory. While all aforementioned objects have bolstered humanity’s space exploration missions, they have also led to a traffic jam in Earth’s orbit.

Now, many (including SpaceX founder Elon Musk) argue that space is enormous. However, it is to be noted that space in Low Earth Orbit or LEO (which hosts most of the artificial objects) is limited. It is here that the flotsam and jetsam from old space vehicles, scattered debris from collisions and mix of newly launched and dying satellites are causing congestion.

What is crowding the space?

According to a recent report by the US Department of Defense’s global Space Surveillance Network (SSN), there are more than 27,000 pieces of orbital debris or “space junk” currently revolving around planet Earth. In addition, there are thousands of other debris which are untraceable by SSN’s sensors but are large enough to jeopardise the safety of satellites and space stations housing human beings. While space junk is a major threat, an increasing number of active extra-terrestrial objects also pose a risk.

Since its inception, Elon Musk-led Space X has deployed nearly 2,000 satellites into Space for its broadband communications network and there are thousands more on the way. Recently, Amazon Inc. and UK base communication firm One Web also announced a similar venture of building their own telecom constellation using hundreds of their own satellites. In addendum, there are two active space stations namely the International Space Station (ISS) and China’s Tiangong orbiting the blue planet. There are also debris from anti-satellite tests and failed space missions.

_{Image showing space debris around Earth. Credit: NASA}

Is it a real threat?

Apart from sabotaging future missions in LEO, Space congestion poses the risk of becoming the flashpoint for potential global conflict. Notably, the international space treaty that was inked on January 27, 1967, has largely become non-functional with more and more private enterprises gaining control over space launches and rocket manufacturing. Meanwhile, experts fear that Kessler’s syndrome could soon turn into reality. Over the years they’ve argued that even one small collision could trigger a deadly chain reaction, eventually turning the space around the Earth into an extra territorial junkyard.  

Even if that does not happen, the crowding is already interfering in Space missions. In October last year, the Chief Executive of Rocket Lab, an American launch startup, Peter Beck admitted that the overwhelming numbers of objects in LEO are making it increasingly difficult to find a clear path for rockets to launch new satellites. The rockets "have to try and weave their way up in between these [satellite] constellations,” Beck told CNN, referring to SpaceX’s Starlink satellites.

Image: ESA