CAPE CANAVERAL, Fla. (AP) — SpaceX will use a powerful, souped-up capsule to lift the International Space Station out of orbit when time for the sprawling lab runs out.
NASA and Elon Musk’s company on Wednesday outlined a plan to burn up the space station on re-entry and sink what’s left in the ocean. The space agency ruled out other options, such as taking the station alone, bringing everything home or handing the keys over to someone else.
NASA SpaceX a $843 million deal Bringing down the station – the largest structure ever built on the planet.
Here is a rundown of the upcoming work and challenges:
Why remove the space station?
The space station is already showing signs of age. Russia and the United States launched the first pieces in late 1998, and the astronauts moved in two years later. Europe and Japan added their own units, while Canada provided robotic arms. By the time NASA’s shuttles were retired in 2011, the station had grown to the size of a football field, with a mass of nearly 1 million pounds (430,000 kilograms). NASA figures the station will last until at least 2030. By then private companies should be launching their own space stations, with NASA serving as one of many customers. That strategy — already in place to deliver station cargo and crew — would free NASA to focus on missions to the Moon and Mars. If there are no commercial outposts, NASA may decide to extend the life of the station. The aim is to overlap without interfering with scientific research.
Why not bring it down to earth?
NASA considered dismantling the space station and hauling the pieces back to Earth or allowing private companies to recover the parts for their own planned outposts. But according to NASA, the station was never intended to be separated in orbit, and any such attempt would be expensive and dangerous for the astronauts handling the disassembly. Besides, there’s no space shuttle as big as NASA’s old shuttles to bring it all down. Another option is to raise the empty station to a higher, stable orbit. But that too was ruled out due to logistical problems and the high risk of space debris.
How to beat?
Visiting spacecraft periodically upgrade the space station so it remains in a high orbit of about 260 miles (420 kilometers). Otherwise, it will continue to descend from orbit until it sinks uncontrollably. NASA wants to ensure a safe re-entry over the remote South Pacific or Indian Ocean, which means launching a spacecraft to the station and heading it toward a watery grave. NASA expects some dense debris, from a microwave oven to a sedan, to survive a narrow debris field 1,200 miles (2,000 kilometers) long. NASA and its partners considered using three Russian supply ships for the job, but a more robust craft was needed. The call went out to industry, and in June, SpaceX won the contract for the Orbit vehicle.
What does the Orbit spacecraft look like?
SpaceX plans to use a normal Dragon capsule — the kind that carries supplies and astronauts to the space station — but with a much larger trunk, 46 engines and 35,000 pounds (16,000 kilograms) of fuel. SpaceX’s Sarah Walker said the challenge was to create a spacecraft powerful enough to navigate the space station while resisting drag and forces from increased atmospheric drag during final descent. According to NASA, this spacecraft will need a particularly powerful rocket to get into orbit. The capsule will be launched 1 1/2 years before the planned destruction of the station. Astronauts will still be on board as it is phased out. Six months before the station is destroyed, the crew will abandon ship and return home. Once the station is down to about 137 miles (220 kilometers), Dragon will bring it down four days later.
Has this been done before?
NASA’s first space station, Skylab, crashed in 1979, showering debris over Australia and the surrounding Pacific. The space agency hoped the first shuttle crew could attach a rocket to control Skylab’s descent or boost its orbit. But the spacecraft wasn’t ready by then, and its first flight wasn’t until 1981. Ground controllers were able to send Skylob into a slow descent, aiming for the Indian Ocean. But some pieces also landed in Western Australia. Russia has a lot of experience with incoming space stations. Mir operated for 15 years before being guided back to a fiery mission over the Pacific in 2001. Before that, several Salyut stations bit the dust.
Can anything be saved?
NASA wants to bring back some small items from inside the space station for museum display, such as the ship’s bell and logs, panels and other memorabilia. They could land on SpaceX supply ships in the final year or two. “Unfortunately, we won’t be able to bring really big objects home,” said NASA’s Ken Bowersachs. “The emotional part of me wants to try and save some of it,” but the more practical approach is to drop it all in one devastating stroke, he said.
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