The Space Debris Crisis by Louisa Spillman Falcon 1 reached orbit in October 2008, securing a partnership between NASA and SpaceX, commencing a decade of commercial space travel innovation. While society looks enthusiastically forward, most are unaware of the millions of high-speed orbiting shards that are chillingly close to imprisoning society on Earth for decades. The culprit is called space debris and it could become unstoppable within just five years. Space debris, also called ‘space junk’, is the name for millions of non-functional objects in orbit around Earth. This includes both miniscule meteoroids and decommissioned satellites. Travelling at roughly 36,000 kilometres per hour, collisions between this debris and spacecraft can be devastating. These shards can cumulatively take out entire satellites, which in turn can produce more debris as pieces of the satellite break away. The International Space Station (ISS) has conducted several path changes to avoid debris, but other spacecraft are not so lucky; around 4 or 5 satellites are destroyed annually. According to Ben Greene, the head of Australia’s Space Environment Research Centre, this is much more critical than it seems – due to the Kessler effect, all important spacecraft are at risk of being destroyed within the next five to ten years. First suggested by Don Kessler, the Kessler Effect warns that the total mass of debris could reach a critical point, beginning an uncontrollable chain reaction to the point that everything in orbit is damaged and it is too dangerous to send up any more spacecraft. Satomi Kawamoto, of the Japan Aerospace Exploration Agency (JAXA), estimates that five significant objects need to be removed per year to prevent this, but the technology is not there yet – all the while, the space industry produces more debris. Defunct satellites, being massive, uncontrolled, and spinning rapidly, are the most hazardous. Due to orbital decay, they do eventually re-enter the atmosphere; however, this could take thousands of years for high altitude spacecraft. Here, the industry is its own worst enemy. SpaceX, for example, plans to launch almost 12,000 satellites by 2020, which could massively impact the chances of the onset of the Kessler Effect. They have agreed to halve the altitude of 1,500 of these, but it is simply not enough. There is hope. Most notably the RemoveDEBRIS mission. A satellite was deployed from the ISS in June 2018 with the goal of testing active debris removal (ADR) technology. In September 2018, it was able to capture a test object it had previously released with a net – history’s first victorious ADR mission. Since then, it has successfully tracked another test object with both 2D cameras and 3D visual software, and even collected a test object by firing a pen-sized harpoon. More experiments are planned for the future, such as the ESA’s e.Deorbit mission, which hopes to use a giant robotic arm to collect one of the most dangerous satellites currently in orbit, Envisat, which would otherwise take approximately 150 years to re-enter the atmosphere.

Looking forward, science finds itself in a great irony. The more commercial space travel technology is pursued, the more it risks sabotaging any space travel for decades to come. ADR technology is still in its early stages, but it is society’s best hope at surviving the highest-stakes gamble humanity has ever taken. In the next century, humanity could be thriving on another planet, or stranded on Earth – only time will tell. From Issue 19

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