SpaceX, NASA watch weather for historic astronaut splashdown on Sunday – Space.com

SpaceX is ready to return its first NASA astronaut crew to Earth, but a potential tropical cyclone brewing in the Atlantic could cause delays.

The SpaceX Crew Dragon spacecraft, called Endeavour, is scheduled to splash down off the Florida coast on Sunday afternoon (Aug. 2). Its crew, NASA's Bob Behnken and Doug Hurley, is wrapping up a historic two-month test flight, the first orbital trip by astronauts on a commercial spacecraft. Their splashdown will also mark the first water landing by American astronauts since the Apollo-Soyuz mission in July 1975.

"Everybody remains 'go' for a return, and we cannot wait to get Bob Behnken and Doug Hurley back to Earth, but of course, we have some weather pending," NASA Administrator Jim Bridenstine told reporters Wednesday (July 29) from the Kennedy Space Center in Florida. "We look forward to seeing if that's going to be within the realm of what is possible."

Related: How NASA and SpaceX's Demo-2 will make a historic splashdown

That "weather pending" Bridenstine referenced is from a storm system the National Hurricane Center (NHC) has dubbed Potential Tropical Cyclone Nine. Current forecasts from the NHC place the storm system squarely on Florida on Sunday just ahead of SpaceX's splashdown target time of 2:48 p.m. EDT (1948 GMT).

"We're going to watch the weather very carefully," said Steve Stitch, manager of NASA's Commercial Crew Program. "We have a series of [landing] sitesand many days in the future, so we'll watch this tropical storm ... we'll kind of take it day-by-day."

Currently, Behnken and Hurley are due to undock from the space station on Saturday evening at 7:35 p.m. EDT (2335 GMT) and prepare to head home. If all goes well, the Endeavour capsule will fire its engines to leave orbit on Sunday for an afternoon splashdown.

In photos: SpaceX's historic Demo-2 test flight with astronauts

SpaceX has seven potential splashdown sites around the Florida panhandle to choose from. They include drop zones offshore from Cape Canaveral, Daytona and Jacksonville on Florida's east cost, and near Panama City, Pensacola, Tallahassee and Tampa on the west coast. Wave height, wind speeds, lightning, rain conditions and other factors will all determine which splashdown sites SpaceX will pick.

"We're really looking for two sites to be go before we undock," Stitch said, adding that the agency will hold off on a final decision until an hour before undocking, or even call of the departure if needed. "The beauty of this vehicle is [that] we can stay docked to the space station."

Behnken and Hurley launched May 30 on SpaceX's Demo-2 mission to the International Space Station. The mission is a two-month shakedown cruise to test if SpaceX is ready to fly operational astronaut missions for NASA. SpaceX has launched uncrewed cargo missions for NASA for years and is one of two companies (Boeing is the other) with a multi-billion-dollar contract to fly astronauts to the station.

The Crew Dragon spacecraft has performed flawlessly in orbit, NASA and SpaceX officials said. The Demo-2 astronauts have tested its ability to hold up to four astronauts at a time, with the only major unknown ahead: splashdown.

"That's a really big deal," said Benji Reed, SpaceX's director of crew management. "It's very important, and it's part of that sacred honor that we have for ensuring that we bring Bob and Doug back home to their families, to their kids and making sure that they're safe."

If bad weather looks like it could delay a Sunday splashdown for Crew Dragon, NASA and SpaceX will postpone this weekend's undocking to no earlier than Monday (Aug. 3), with splashdown likely coming a day later, Stitch said.

"So we'll have to evaluate the weather each day and just see things how things unfold," Stitch said. "We have plenty of opportunities here in August and we're in no hurry to come home."

Even as SpaceX prepares to return Behnken and Hurley to Earth, the company is already gearing up for its first operational mission, called Crew-1. The spacecraft for that mission is nearly complete at the company's headquarters and factory in Hawthorne, California and will be shipped to Cape Canaveral soon, Reed said.

The Crew-1 astronauts NASA's Michael Hopkins, Victor Glover and Shannon Walker, and Japan's Soichi Noguchi are with the vehicle this week, Reed added. That mission is currently scheduled to launch in late September.

Yesterday, NASA also announced the four astronauts to launch on Crew-2, SpaceX's second operational flight, in early 2021. That mission will launch astronauts Shane Kimbrough and Megan McArthur, both of NASA; Akihiko Hoshide of Japan and Thomas Pesquet of the European Space Agency. McArthur is married to Behnken, and her Crew-2 mission will launch on the same Dragon ship Endeavour as her husband, NASA and SpaceX said.

Meanwhile, as SpaceX prepares to return the Demo-2 astronauts to Earth, NASA is counting down for another milestone event: a launch to Mars.

NASA's Mars 2020 Perseverance rover is poised to launch toward the Red Planet tomorrow (July 30). The mission, which will collect samples of Mars for eventual return to Earth, deploy a helicopter and seek out signs of ancient life, will launch atop a United Launch Alliance Atlas V rocket from Cape Canaveral Air Force Station. Liftoff is set for 7:50 am. EDT (1150 GMT).

Editor's note: You can watch NASA's Mars rover Perseverance launch live here, courtesy of NASA TV. The webcast will begin at 7 a.m. EDT (1100 GMT). SpaceX's undocking and splashdown of the Demo-2 crew will also be webcast live.

Correction: An earlier version of this article misspelled the name of ESA astronaut Thomas Pesquet.

Email Tariq Malik attmalik@space.comor follow him@tariqjmalik. Follow us@Spacedotcom, Facebook and Instagram.