The US will welcome back two astronauts from the International Space Station this weekend as SpaceX stages the first crewed return flight of its Dragon vehicle with a splashdown off the Florida coast.
The planned re-entry flight has passed a flight-readiness review, the National Aeronautics and Space Administration said Wednesday. A tropical storm forming southeast of Florida remains the biggest risk for a potential delay in the crew’s return, officials from the U.S. space agency told reporters.
Astronauts Bob Behnken and Doug Hurley are scheduled to undock the Dragon from the space station at 7:34 p.m. Eastern time on Saturday if weather forecasts back on Earth cooperate, NASA said. They will begin an engine burn to break out of orbit Sunday afternoon, with their landing in the ocean planned less than an hour later at 2:42 p.m. The vehicle will see temperatures of around 3,500 degrees Fahrenheit (1,927 degrees Celsius) during the re-entry.
If the weather poses a problem, NASA will delay undocking from the ISS to Monday, for a Tuesday arrival. NASA has set a maximum wind limit of 10.2 miles an hour, as well as limits for wave size and frequency for the descent and landing.
The Dragon has oxygen, water and supplies to remain in orbit for about three days if the weather deteriorates. NASA could extend that slightly, said Steve Stich, the agency’s commercial crew program manager.
Behnken and Hurley launched for the station May 30 on a Falcon 9 rocket made by Elon Musk’s Space Exploration Technologies Corp. Their flight is the first time American astronauts have flown from the U.S. since NASA’s space shuttle program ended in 2011. And it’s SpaceX’s first test flight to the station with astronauts on board.
The milestone mission comes 18 years after Musk founded SpaceX with the ultimate goal of populating other planets.
NASA has selected seven potential sites off the east and west coasts of Florida for the Dragon’s return. SpaceX plans to help astronauts exit the capsule and collect the reusable vehicle within an hour of the splashdown. In case of an emergency, the agency has arranged to have U.S. military aircraft in Hawaii and South Carolina prepared to fly a search and rescue mission.
The ocean landings come after a 45-year hiatus and hark back to NASA’s Apollo program, which saw astronauts splash into the Pacific Ocean with retrieval by ships. The last U.S. space return by sea was the joint Apollo-Soyuz docking mission, which ended with the Apollo capsule’s return in July 1975 northwest of Hawaii.
If the test mission goes according to plan, NASA aims to send its next space station crew in late September with four astronauts aboard the Dragon. The vehicle Behnken and Hurley flew will be refurbished for a Crew-2 Mission in the first half of 2021 with another four astronauts -- including Megan McArthur, Behnken’s wife, who will serve as the mission’s pilot.
NASA has contracted with SpaceX and Boeing Co. for crew-ferry missions to the space station. Boeing plans a second uncrewed test flight of its Starliner vehicle later this year after a failed attempt in December.