YYou could live your whole life thinking nothing about collets. Indeed, you could go your entire life without even knowing what a collet is, and if we stopped right here you’d be no worse off. For the record, though, a collet is a small ring of metal, about the size of a fist, and, as NASA announced at a July 20 press conference, at the moment, it’s the biggest thing standing in the way of the U.S. having humans back on the surface of the moon sometime in the middle of this decade.
The collet in question is attached to the hydrogen fuel line of the main stage of NASA’s new mega-moon rocket, the Space Launch System (SLS), a 97 m (318 ft) beast of a machine, capable of producing 4 million kg (8.8 million lbs) of thrust. NASA hopes to launch the SLS on an uncrewed shakedown cruise around the moon and back, a mission known as Artemis 1, sometime in late August or early September—a flight that would be followed by an identical crewed mission in 2024.
NASA must go through what is called a wet rehearsal before Artemis 1 can fly. The rocket will be loaded with 740,000 gal (7 million liters) of liquid hydrogen, oxygen fuel, and the rocket will then be driven to the launch site. NASA tried the wet dress rehearsal four times, and failed three times.
In June it was finally successful. The only issue with this launch was the loose cursed collet. This could have prevented the hydrogen fuel co-line from being separated from the rocket in a true launch. So now, the SLS is back in its hangar, with engineers working on that final problem—and confident they can fix it.
If they can, the moon mission is on—marking the first time the U.S. will have sent a crew-rated (but not actually crewed) spacecraft on a lunar journey since Apollo 17 in December 1972. Artemis 1 may launch on three dates in the near future. They are Sept. 9, September 2, and Sept. 9. The mission could slip to September or October if the agency fails to meet the launch window.
This mission will be about 40 days long and will involve the SLS flying the Orion crew vehicle into Earth orbit. Then, it will follow a looping trajectory to fly the Orion around the Moon at altitudes between 100 km (62 mile) and just 100 km. To 70,000km (43,000 mi.). The Orion capsule will then return to Earth, slamming into the atmosphere at about 32,000 km/hr (20,000 mph) and sustaining temperatures of up to 2,700ºC (nearly 5,000ºF) on its heat shield, before splashing down in the Pacific off the San Diego coast.
There will not be anyone inside the Orion capsule to greet or congratulate when it is lifted from the sea. The next SLS flight will see four astronauts aboard. The United States abandoned the moon nearly 50 years ago. It took only six weeks to begin to claim it.
Original publication of this article was TIME Space. Register here.
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