"Butch and Suni" astronauts prepare for Tuesday homecoming after nine-month mission

WASHINGTON: Butch Wilmore and Suni Williams, two NASA astronauts who have been stuck on the International Space Station for nine months, are scheduled to begin their return to Earth early Tuesday morning on a long-awaited flight home to cap an unusual mission.

After a replacement crew arrived on the space station Saturday night, veteran astronauts Wilmore and Williams and two other astronauts are poised to undock from the ISS at 1:05 a.m. ET (0505 GMT) Tuesday to begin a 17-hour trip back to Earth.

The astronaut crew are scheduled to splashdown off a Florida coast - the exact location pending weather conditions - at 5:57 p.m. ET later that day.

Wilmore and Williams were the first crew to fly Boeing's Starliner spacecraft in a key test flight in June. But after issues with the craft's propulsion system, NASA deemed it too risky to bring the astronaut duo back home and opted to fold them into the agency's Crew-9 mission instead while Starliner returned to Earth empty in September.

NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov, the other two members of Crew-9, will join Wilmore and Williams. Hague and Gorbunov flew to the ISS in September on a Crew Dragon craft with two empty seats.

NASA previously planned to return Crew-9 on Wednesday night, but unfavorable weather later in the week would have complicated the Crew Dragon capsule's return, leading the agency to move the return trip up to Tuesday.