The NASA SpaceX Crew-4 astronauts (from left) Jessica Watkins, Bob Hines, Kjell Lindgren and Samantha Cristoforetti are seated inside the Crew Dragon spacecraft.

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Four astronauts are scheduled to return home from the International Space Station this week, capping off a nearly six-month mission in space, but rough weather at the crew’s splashdown site is forcing a delay.

The astronauts — NASA’s Kjell Lindgren, Bob Hines and Jessica Watkins, as well as Italian astronaut Samantha Cristoforetti with the European Space Agency — were scheduled to depart from the space station aboard a SpaceX Crew Dragon capsule Thursday morning. But NASA was forced to wave off the departure because of the unfavorable weather conditions back on Earth.

NASA and SpaceX are now targeting Friday at 11:35 a.m. ET for the Crew Dragon’s departure, and splashdown off the coast of Florida could occur just a few hours later, at 4:50 pm ET, according to a NASA press release.

Weather forcing delays of spacecraft launching or returning from the ISS is extremely common, especially as unpredictable storms batter the spashdown sites off the coast of Florida.

“Mission teams continue to monitor a cold front passing through Florida on Thursday, Oct. 13, bringing high winds and rainy weather near the splashdown zones off the Atlantic and Gulf coasts,” according to NASA. “Current weather predictions are showing greater forecast certainty Friday due to a high-pressure system behind the cold front, which is expected to bring more favorable conditions for splashdown and recovery.”

Ground crews are expected to review the weather again overnight.

The Crew Dragon spacecraft that will bring the astronauts home typically has seven potential landing zones – just off the coast of Pensacola, Tampa, Tallahassee, Panama City, Cape Canaveral, Daytona and Jacksonville.

It’s not yet clear which splashdown site NASA and SpaceX are targeting for Friday.

This mission, called Crew-4, has marked a historic first on the ISS, as Jessica Watkins became the first Black woman to join the space station crew for an extended stay.

More than a dozen Black Americans — including five Black women — have traveled to space since Guion Bluford became the first to do so in 1983. The ISS has hosted more than 250 astronauts since 2000, but no Black woman has previously had the opportunity to live and work in space for an extended period until now.

Aerospace company SpaceX developed the Crew Dragon spacecraft under a $2.6 billion contract with NASA as part of the Commercial Crew Program.

The idea behind the program was to move NASA into a customer role — allowing private companies to design, build and test a new spacecraft to serve NASA astronauts while still giving the company ownership over the vehicle.

For nearly a decade after the retirement of NASA’s Space Shuttle Program in 2011, the United States had to rely on purchasing seats on Russian Soyuz spacecraft to get its astronauts to and from the ISS. SpaceX renewed orbital human spaceflight capabilities from US soil in 2020 with the launch of its Demo-2 mission, which carried two NASA astronauts to the space station.

Crew-4 is the fifth flight SpaceX has carried out as part of its NASA partnership, and the space agency has continued purchasing additional flights from the company led by founder and CEO Elon Musk.

The Crew-4 astronauts’ return to Earth comes less than a week after the Crew-5 astronauts arrived on a separate SpaceX Crew Dragon capsule. The two mission teams have spent the past few days in a brief handoff period to ensure a smooth transition between the crews.

Officials at NASA have continued to extend the agency’s partnership with SpaceX, growing the value of their overall deal to encompass 15 total crewed missions at a value of more than $4.9 billion.

Since SpaceX developed the Crew Dragon under a fixed-price commercial contract, however, it retains ownership over the vehicle. That means the privately held company also has the ability to sell seats to whomever it wishes. SpaceX has already conducted two Crew Dragon missions funded entirely by wealthy thrill-seekers. And there are future private missions in the works.