By Andy Pasztor 

Elon Musk's SpaceX will try again this weekend to launch NASA astronauts into orbit, days after stormy weather forced it to scrub a historic flight showcasing industry-government collaboration to explore the heavens.

If Mother Nature cooperates, and preparations proceed as smoothly as they did Wednesday, the 230-foot Falcon 9 rocket is scheduled to lift off at 3:22 p.m. ET Saturday from Florida's Kennedy Space Center, sending veteran astronauts Bob Behnken and Doug Hurley toward the international space station circling 250 miles above the Earth.

Before heading to the pad, the astronauts had a final chance to wave at family members as the two of them left a crew facility and rode to the pad in a white, electric-powered sedan festooned with NASA logos and built by Tesla Inc., another of Mr. Musk's companies. Roughly three hours before liftoff, Messrs. Behnken and Hurley entered the capsule, settled into their places, donned their seat restraints and eventually the hatch was sealed behind them.

Less than an hour before scheduled liftoff, SpaceX flight controllers declared the mission was "go for launch," and fuel started loading about 35 minutes before launch.

A successful liftoff and ascent of the Crew Dragon will propel the crew and the country into a new era of corporate-driven space endeavors. National Aeronautics and Space Administration chief Jim Bridenstine has described the mission as "a herculean task by the SpaceX team, which we are very grateful for, and also by the NASA team that has been working hand-in-glove with them."

The NASA chief alluded to multiple technical challenges and setbacks that have delayed the project and said SpaceX had adopted a different, more-nimble strategy than NASA's traditional approach of seeking to avoid test failures. "They test, they fail, they fix, they fly," he said, adding that NASA was satisfied with the safety of the rocket along with the spacecraft on top of it.

During a chat with the crew as they were donning spacesuits, Mr. Bridenstine said the astronauts were joking with each other. "They're trained. They're ready, but they're also loose."

Wednesday's countdown played out without a hitch until roughly 17 minutes before the scheduled blastoff. The launch was called off because of rain and the potential for lightning strikes, with the crew praising the ground staff for getting the craft ready.

President Trump and Vice President Mike Pence are expected to watch Saturday's activities at Launch Complex 39A again. Mr. Trump exited the White House shortly after noon to head to Florida. "I think I have an obligation to be there," he said.

Forecasts are indicating only about a 50-50 chance of acceptable weather conditions. Sunday would be the next alternate launch date, with early forecasts showing a likelihood of somewhat improved conditions.

More than two hours before launch, with dark, towering clouds starting to build near the pad and rain starting to fall, Mr. Bridenstine said weather was still an issue, but NASA wanted to see if the clouds and rain eventually would move enough away to allow a launch.

With thunderstorms common in Florida in May, the NASA chief said it wasn't likely that "in a couple of days it's going to be any better." Still, he said, another delay is possible. "We cannot forget this is a test flight," Mr. Bridenstine said Friday. "We will go when everything is as safe as we can possibly make it."

Rain and high-level wind pose hazards for rockets as they leave the ground and rumble through the atmosphere, and SpaceX crews also monitor weather at various emergency landing sites the crew might need to use in case the capsule's abort system kicks in to separate it from a malfunctioning rocket.

Weeks of media buildup have included a host of interviews with NASA brass and senior leaders of Space Exploration Technologies Corp., the formal name of Mr. Musk's closely held space company, based in Southern California. They have all stressed the significance of a mission intended to end a nine-year period without a human launch from U.S. soil.

Shortly before the mission was scrubbed Wednesday, Mr. Musk said about the scheduled launch, "This is not something I ever thought would actually happen."

SpaceX's founder and chief engineer recalled when the company started 18 years ago as a tiny startup dismissed by government and industry experts. Mr. Musk said he expected a "90% chance we'd fail to even get to low-Earth orbit with a small rocket." It took the company four tries to make that happen.

Mr. Musk said that if someone had described SpaceX eventually being on the cusp of becoming the first company to launch astronauts beyond the atmosphere, "I would have thought. 'Man, I don't know what you're smoking.'"

SpaceX experienced a setback Friday when a prototype spaceship using next-generation rocket technology exploded during an apparent ground test in Texas. There were no reports of injuries, and the hardware was different from the Falcon 9 rocket being used in Saturday's planned launch. It is the fourth similar testing problem and highlights the trial-and-error process in developing sophisticated vehicles.

A successful launch Saturday would mean NASA astronauts won't have to piggyback on Russian rockets and spacecraft, as they have since the aging U.S. space-shuttle fleet was retired nine years ago. Looking ahead, NASA and White House officials envision emphasizing deep-space exploration as part of a commitment to relying on similar corporate-government teams. Those would include company-led endeavors, with relatively limited federal oversight, taking astronauts to the moon as soon as 2024 and later to Mars or beyond.

Some longtime NASA watchers see the current mission as a crucial steppingstone, perhaps as significant in some ways as the Gemini missions of the mid-1960s that paved the way for the Apollo moon landings. But this time, making the government "a customer rather than operator is as astonishing as it is bold for NASA," said Mark Albrecht, a former White House space adviser and retired senior industry executive. "NASA will take the blame for failure and allow SpaceX to receive most of the glory of success."

Beyond the policy changes and revamped contracting arrangements, the sheer promise of accelerating human space exploration excites many government and industry officials. Nothing generates as much pride as adding humans to the equation.

"When you put an astronaut on top of a rocket, that changes everything," Air Force Gen. John Hyten, a longtime space expert and vice chairman of the Joint Chiefs of Staff, told a White House space-policy council.

The Crew Dragon capsule, featuring automation supplemented by touch-screen controls similar to those found on the dashboards of electric cars, has suffered a series of setbacks, including balky oxygen generators, malfunctioning thrusters and problematic parachutes. After its planned launch Saturday, the capsule is slated to stay at the international space station for around two months. If all goes well, including the return trip that ends with a splashdown in the Atlantic, NASA hopes for swift approval of SpaceX's systems as space taxis that would ferry crews to and from orbit.

"Human space flight is really, really tough," said Benji Reed, director of crew mission management at SpaceX. As company and NASA engineers work together to identify and alleviate risks, he said, "we are all holding each other accountable."

Boeing Co. has developed a rival capsule, the Starliner, which has struggled with its own technical challenges and might make a test flight later in the year without astronauts.

NASA has invested more than $7 billion of taxpayer money so far in SpaceX and Boeing efforts to resume astronaut liftoffs from U.S. soil. The agency's Mr. Bridenstine sees a successful launch as recasting the path for America, other nations and industry to reach space.

U.S. astronauts "need to have the capability of accessing space, not just for NASA but for all of humanity," he has said.

Write to Andy Pasztor at andy.pasztor@wsj.com

 

(END) Dow Jones Newswires

May 30, 2020 15:06 ET (19:06 GMT)

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