You never know what you’ve got til it’s gone. And if you don’t believe that, consider the national jubilation at 3:22 PM EDT Saturday afternoon, when an American rocket carrying an American crew lifted off from American soil for the first time since 2011, carrying astronauts Doug Hurley and Bob Behnken to the International Space Station (ISS). The successful launch comes just a few days after Wednesday’s initial attempt was scrubbed due to weather.
The last time there was this kind of U.S. hoopla for a mere flight to low-Earth orbit might have been the first time, on February 20, 1962, when John Glenn became the first American to orbit the planet. Orbital flight has since become routine, with 135 missions flown by the space shuttle fleet alone. But when the last shuttle was retired in 2011, America became a grounded nation—even a humbled nation—reduced to hitching rides aboard Russia’s Soyuz spacecraft at a cool $80 million a seat. So Saturday’s launch, aboard a SpaceX Falcon 9 rocket and Crew Dragon spacecraft, sends one signal more powerfully than any other: when it comes to space, America is back.
“This is a big moment in time,” said NASA Administrator Jim Bridenstine in a press conference earlier this week. “It’s been nine years since we’ve had this opportunity.”
It’s not just the fact that America is flying again, it’s the way that it’s flying. Saturday’s launch was the result of 10 years of work under NASA’s commercial crew program, an initiative begun in 2010 to get the space agency out of the business of flying astronauts to and from low-Earth orbit and turn the job over to private companies. NASA would then buy the services of the commercial providers like any other customer, freeing up the space agency to concentrate its human-exploration efforts on crewed missions to the moon and Mars. The space agency concedes that for today’s flight it is in many ways the junior partner.
“SpaceX is controlling the vehicle, there’s no fluff about that,” said Norm Knight, a NASA flight operations manager, in a conversation with the Associated Press.
But in truth, the program was never truly as private-sector as it seemed. After NASA selected both SpaceX and Boeing to develop and build the new crew vehicles, it paid the companies $6.8 billion—$2.6 billion to SpaceX and $4.2 billion to Boeing—in research and development funding, and contracted with them to ferry cargo and crew to the space station once they had built working ships.
Both companies were supposed to begin flying crews as early as 2016, and both are clearly well behind schedule. Boeing looked like it might be the first out of the gate after the uncrewed test launch of its CST-100 Starliner in December 2019. But while the spacecraft made it safely both to orbit and back home, a software failure caused it to use too much maneuvering fuel, preventing it from achieving its principal objective of docking with the ISS. Boeing now needs to repeat the uncrewed flight—and get it right this time—before it will be permitted to carry astronauts. That left the field clear for SpaceX to be first—an opening it took advantage of with Saturday’s launch.
Credit for SpaceX’s big win goes in large measure to the company’s proven line of hardware, including its workhorse Falcon 9 rocket. Counting its maiden flight in June 2010, it had 83 launches before today’s, in some cases ferrying satellites to orbit for paying customers, in other cases making cargo runs to the ISS. Part of the secret of the Falcon 9’s reliability is its simplicity. Rather than design entirely different rockets for different payload sizes, SpaceX goes by a simple more-is-better rule. Its first rocket, the Falcon, used a single engine, powered by kerosene and liquid oxygen. The Falcon 9, true to its name, uses a cluster of 9 of the same engines; and the Falcon Heavy, the bruiser of the SpaceX fleet, lifts off under the power of a whopping 27 engines, arranged in three clusters of nine.
What further sets the Falcon 9 apart from its competitors—such as United Launch Alliance’s Atlas V or Europe’s Ariane 5—is its reusable first stage. Instead of just dumping the spent stage in the ocean when the rocket is partway to space, SpaceX designs its first stages to fly back to a landing platform and touch down on extendable legs, allowing them to be refurbished and re-used. So far, there have been 41 such successful landings, and 31 first stages have flown more than once. The result: cost savings. SpaceX advertises its services at $62 million per launch, compared to $165 million for Atlas or Ariane.
The Dragon spacecraft is similarly reusable. The Cargo version of the spacecraft has been flown 22 times—21 of which involved resupply missions to the space station. Nine of the launches have involved vehicles that already had undergone at least one previous flight. The interior space of the Crew Dragon is configurable to hold from two to seven astronauts. It stands 8.1 m (26.7 ft) tall and is 4 m (13 ft) wide. That’s a big jump over the old Apollo spacecraft at 3.2 m (10.5 ft) tall and and 4 m (13 ft) across. And again, while the very purpose of the commercial crew program was get the government out of the business of designing spacecraft for low-Earth orbit, no one pretends that with NASA’s own astronauts in the seats, the space agency itself would not be at least a collaborator in the design process.
“[SpaceX] had this vision of how the Crew Dragon should look, feel and operate,” says John Posey, lead engineer for NASA’s Crew Dragon team. “But we had two-way communication as we started building components, testing components, test flying components, just making sure that we were always working together and coming in towards the best, optimized solution.”
Behnken and Hurley were good choices for the maiden Dragon mission. Both are veterans of two space shuttle missions, and Hurley, fittingly, was one of the crew members aboard the final space shuttle mission in 2011. Despite all that, once they reach the ISS, they will be just two more crew members, the 64th such crew to launch to the station in the 20 years it has been continuously occupied. They will join NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner, getting the station’s crew complement closer to its customary six.
Behnken’s and Hurley’s stay will be relatively short, as space station visits go. They will remain aboard for at least a month, though in no case will they remain for longer than 110 days, since the current Crew Dragon is not rated for a longer stay in the punishing environment of space. (Ultimately, the Dragon will be required to be certified for a 210-day stay.) Part of what will determine when the two new arrivals will come home will be the progress Boeing makes in developing its Starliner. There are only two docking ports aboard the station; one is now occupied by the Russians’ Soyuz rocket and the other will accommodate the Dragon. If Starliner is ready for its scheduled uncrewed test flight before the Dragon’s 110 days are up, Behnken and Hurley will have to climb aboard and clear out to make room.
But all of that is for later. Today is for savoring the simple fact that the U.S. has once again rejoined the family of space-faring, astronaut-launching, future-gazing nations. The nation that for generations led the world in the exploration of space is now poised to reclaim that mantle.
from Science – TIME https://ift.tt/36I8yne
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