A spacecraft graveyard
October 22, 2017
Dave Mosher
Dave Mosher reported news and features stories about science and technology for Insider, with human and robotic spaceflight as the primary focus of his multimedia storytelling.
Large satellites, space stations, and other objects can pose a threat when they fall to the ground. As a result, many nations de-orbit old spacecraft over the most remote place on Earth, called Point Nemo. This “spacecraft cemetery” is about 1,450 miles away from any piece of land and home to hundreds of dead satellites. Space agencies and companies are concerned about space junk and working on ways to prevent its formation and clean it up.
The most remote location on Earth has many names: It’s called Point Nemo (Latin for “no one”) and the Oceanic Pole of Inaccessibility. Most precisely, its exact coordinates are 48 degrees 52.6 minutes south latitude and 123 degrees 23.6 minutes west longitude.
The spot is about 1,450 nautical miles from any spot of land — and the perfect place to dump dead or dying spacecraft, which is why it’s home to what NASA calls its “spacecraft cemetery.”
“It’s in the Pacific Ocean and is pretty much the farthest place from any human civilization you can find,” NASA said. Bill Ailor, an aerospace engineer, and atmospheric reentry specialist put it another way: “It’s a great place you can put things down without hitting anything,” he said. To “bury” something in the cemetery, space agencies have to time a crash over that spot. Smaller satellites don’t generally end up at Point Nemo, since, as NASA explains, “the heat from the friction of the air burns up the satellite as it falls toward Earth at thousands of miles per hour. Ta-da! No more satellite.”
The problem is larger objects, like Tiangong-1: the first Chinese space station, which launched in September 2011 and weighs about 8.5 tons. China lost control of the 34-foot-long orbital laboratory in March 2016, and it is now doomed to crash by early 2018.
Where, exactly? No one yet knows. Ailor, who works for the nonprofit Aerospace Corporation, said his company likely won’t generate a forecast until five days before the space station is expected to break apart in Earth’s atmosphere. When it does, hundreds of pounds of the spacecraft — like titanium scaffolding and glass-fiber-wrapped fuel tanks — could be falling at more than 180 miles per hour just before slamming into the ground (and thousands of miles per hour faster in the upper atmosphere).
Since China doesn’t have control of Tiangong-1, it can’t assure the space station will disintegrate over Point Nemo.
The dead-spacecraft dumping zone
Astronauts living aboard the International Space Station actually live closer to the graveyard of spacecraft than anyone else. This is because the ISS orbits about 250 miles above Earth — and Point Nemo when the orbital laboratory flies overhead. (The nearest island, meanwhile, is much farther away.)
Between 1971 and mid-2016, space agencies all over the world dumped at least 260 spacecraft into the region, according to Popular Science. That tally has risen significantly since the year 2015, when the total was just 161, per Gizmodo.
“We’ve figured out that this debris can stay up there for hundreds of years,” Ailor said, later clarifying that some objects in higher orbits, like geosynchronous satellites, can stay in orbit for thousands of years.
Getting old spacecraft out of orbit is a key to preventing the formation of space junk, and many space agencies and corporations now build spacecraft with systems to de-orbit them (and land them in the spacecraft cemetery). But Ailor and others are pushing for developing new technologies and methods that can lasso, bag, tug, and otherwise remove the old, uncontrolled stuff that’s already up there and continues to pose a threat. “I’ve proposed something like an XPRIZE or a Grand Challenge, where would you identify three spacecraft and give a prize to an entity to remove those things,” he said. The most significant hurdle to clear what may be politics on Earth. “It’s not just a technical issue. This idea of ownership gets to be a real player here,” Ailor said. “No other nation has permission to touch a US satellite, for instance. And if we went after a satellite … it could even be deemed an act of war.” Ailor said someone needs to get nations together to agree on a treaty that spells out laws-of-the-sea-like salvage rights to dead or uncontrollable objects in space. “There needs to be something where nations and commercial [companies] have some authority to go after something,” he said.
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