If you somehow managed to find yourself floating above one of the most remote places on Earth, the vast blue surrounding you would be by far the least interesting part. Named Point Nemo, a reference to Jules Verne's Captain Nemo, this oceanic pole of inaccessibility lies in the South Pacific Ocean some 1,400 nautical miles from land. It is home to the largest spacecraft graveyard on the planet.
Between 1971 and 2016, more than 263 spacecraft have claimed the waters around Point Nemo as a final resting place. These include Russian Progress cargo vessels filled with human waste from orbiters like the International Space Station, large satellites and, most famously, the remains of the Russian MIR space station.
"Spacecraft do not survive atmospheric re-entry whole," space archaeologist Alice Gorman of Flinders University in Adelaide, Australia told the BBC. "Most of them burn up in the fierce heat. The most common components to survive are fuel tanks and pressure vehicles, which are part of the fuel system. These are generally made of titanium alloys or stainless steel, often encased in complex carbon fibres, which are resistant to high temperatures."
While Point Nemo's deep waters, averaging 12,000 feet, offer the perfect hiding spot, they're also surprisingly lifeless. This phenomenon is due its location in the center of the South Pacific Gyre, a gigantic, rotating current that blocks cooler, nutrient-rich water from entering the region. Because of its distance from land (indeed, the closest humans are often those on the International Space Station, which orbits "only" 258 miles above), Point Nemo also misses out on organic matter spread by wind. It is, as oceanographer Steven D'Hondt of the University of Rhode Island recently declared, "the least biologically active region of the world ocean."
But not all spacecraft go to die here
Spacecraft that do not end up in this watery mass grave either burn up in the atmosphere upon reentry or continue to haunt in what NASA calls a "graveyard orbit" more than 22,000 miles above Earth. There is, however, one big and potentially dangerous exception that humanity will need to deal with in the coming months.
In September 2016, Chinese officials announced that they had lost control of the 34-foot-long, 8.5 ton Tiangong 1 space lab. Over the past several months, the spacecraft's orbit has slowly been decaying, pushing it closer and closer toward Earth's atmosphere. As a result, when Tiangong makes its fiery, uncontrolled return back to Earth later this year, some pieces weighing up to 220 pounds could survive and cause serious damage.
“You really can’t steer these things,” Harvard astrophysicist Jonathan McDowell told the Guardian. “Even a couple of days before it re-enters we probably won’t know better than six or seven hours, plus or minus, when it’s going to come down. Not knowing when it’s going to come down translates as not knowing where it's going to come down.”
While Point Nemo may be robbed of an opportunity to add to its collection of space history, Chinese officials say the odds are "very low" that Tiangong 1 will impact aviation or ground activities.
"It could be a real bad day if pieces of this came down in a populated area … but odds are, it will land in the ocean or in an unpopulated area," Thomas Dorman, an amateur satellite tracker keeping tabs on Tiangong-1 from El Paso, Texas, told Space.com in June 2016. "But remember — sometimes, the odds just do not work out, so this may bear watching."