NASA's Crew-9 mission aboard a SpaceX Crew Dragon capsule Saturday afternoon from Cape Canaveral Space Force Station in Florida.

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After their weeklong journey turned into a monthslong stay on the International Space Station, two Boeing Starliner astronauts will soon be united with the spacecraft that will eventually bring them home.

The SpaceX Crew Dragon capsule, chosen by NASA to carry astronauts Suni Williams and Butch Wilmore back to Earth after their Starliner spacecraft was deemed too risky for crew, is approaching the space station. The vehicle, on a mission called Crew-9, is expected to dock at about 5:30 p.m. ET Sunday.

On board the SpaceX vehicle are NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov. Alongside them are two empty seats, saved for Williams and Wilmore to occupy when the group returns to Earth next year.