How to responsibly decommission a spacecraft
May 7, 2021 - China’s out-of-control rocket core draws attention to how agencies can safely dispose of unwanted spacecraft using Earth’s “Point Nemo”.
With China’s National Space Administration coming under increasing scrutiny from abroad due to its cavalier approach to disposing of a 30-metre-long, 21-tonne piece of space junk, how does NASA do it?
The short answer is, it dumps its unwanted spacecraft at “Point Nemo”.
Point Nemo (named after the famous submariner from Jules Verne’s “Twenty Thousand Leagues Under the Sea”) is located in the middle of the Pacific Ocean, at a position that is the furthest away from any human population or landmass – 2,688km away from anything or anybody. In fact, it’s so far away from anybody that astronauts aboard the International Space Station are closer (360km above it).
NASA, and other space agencies, have been dumping space junk there since the early 1970s. It’s the perfect spot to get rid of top secret technology – whatever doesn’t burn up in the atmosphere will come to rest in a mangled heap about three kilometres below sea level.
Crashing a spacecraft into the Pacific is not a precise art form and nothing hits exactly upon Point Nemo. Typically, a large craft will break up into a variety of smaller chunks and be scattered across about 1,500km of ocean.
Russia is by far the biggest user of Point Nemo, with about 200 space objects down there. NASA is next with more than 50, Europe about 10 and Japan with half-a-dozen.
The types of craft being dumped there include spy satellites, fuel tanks, and cargo craft.
There are a couple of big ticket items down there too: Russia’s 130-tonne Mir space station, which was decommissioned in 2001, and China’s Tiangong-1 space station which went out of control in 2016 after only five years in service – eventually crashing into the Pacific in 2018.
More recently, unreusable rocket parts from SpaceX launches have found their way to Point Nemo, and alas eventually, so too will the International Space Station – due to be decommissioned and crashed there around 2028.