Four astronauts appeared at Kennedy Space Center on Sunday in preparation for SpaceX's second crew flight departing next weekend.

For NASA, it signals the long-awaited beginning of routine crew rotations at the International Space Station, with lifts being supported by private companies. The number of astronauts would be twice that of the test flight earlier this year, and their project will last a full six months.

"Make no mistake: Every flight is a test flight when it comes to space travel. But it's also true that we need to be able to go to the International Space Station routinely," NASA Administrator Jim Bridenstine said in welcoming the astronauts to Kennedy.

(Photo : REUTERS/Joe Skipper/File Photo)
FILE PHOTO: A SpaceX Falcon 9 rocket and Crew Dragon spacecraft carrying NASA astronauts Douglas Hurley and Robert Behnken lifts off during NASA's SpaceX Demo-2 mission to the International Space Station from NASA's Kennedy Space Center in Cape Canaveral, Florida, U.S., May 30, 2020.

Just Don't Interfere, Tropical Storm Eta

The crew of three Americans and one Japanese are expected to rocket away Saturday night, provided there is no interference with incoming Tropical Storm Eta. It's going to be a speedy space station ride, a six-orbit express that takes less than nine hours.

Despite all the obstacles of 2020 - particularly coronavirus and social distancing rules - the astronauts have called their Dragon capsule Durability. They have been in isolation for a week or two and, even before that, have taken protective precautions - masks and social distancing.

"It's been a tough year for everybody for a lot of different reasons," crew commander Mike Hopkins said after flying in from Houston. "We felt like if the name of our vehicle could give a little hope, a little inspiration, put a smile on people's face, then that is definitely what we wanted to do."

The four will stay in orbit until spring as their replacements arrive in another SpaceX Dragon spacecraft. The freight variant of the capsule will still begin to carry food and equipment periodically.

The organization plans to fly seven Dragons over the next 14 months, SpaceX's Benji Reed said: three for crew and four for freight.

"There will be two Dragons in space any time there is a Dragon launch," said Reed, crew project management chief.

Meanwhile, NASA's other hired taxi service, Boeing, is not scheduled to fly the first crew until next summer. In a couple of months, the corporation is preparing a second unpiloted test flight; the first encountered so many software glitches that the Starliner capsule struggled to hit the space station.

Following the shuttle fleet's retirement in 2011, NASA switched to private firms for space station deliveries. At increasingly steep costs, U.S. astronauts kept hitching rides on Russian rockets. It cost NASA $90 million for the last Soyuz ticket.

Shall The Astronauts Face Disappointments?

Last May, SpaceX officially ended NASA's almost decade-long astronaut launch shortage, effectively sending a pair of test pilots to Kennedy's space station for a two-month visit. After its splashdown, the returning capsule was scrutinized by SpaceX, culminating in a few adjustments for this second flight.

Engineers found extreme corrosion from the searing reentry temperatures in the heat shield; for the upcoming mission, the organization shored up the weak portion, said Hans Koenigsmann, a SpaceX vice president. 

The parachute height measurement device's improvements were also made after the chutes opened a little too low on the first astronaut trip. More recently, owing to pollution from the red lacquer used in manufacturing, the Falcon rocket had two engines removed. The engine swaps postponed the two-week flight.

Probably the greatest disappointment of the first SpaceX crew flight was all the private boats full of gawkers that surrounded the Gulf of Mexico capsule after the August splashdown. For potential returns, Koenigsmann promises a wider keep-out zone and further patrols.

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