Hague and Gorbunov rode up to the station aboard Freedom in late September, on the launch of SpaceX's Crew-9 mission. Williams and Wilmore, on the other hand, reached the ISS on the first crewed flight of Boeing's Starliner capsule, which lifted off in early June.

A four-member crew, including NASA astronauts Sunita "Suni" Williams and Barry "Butch" Wilmore, left the ISS early Tuesday on a SpaceX Dragon spacecraft.

NASA astronauts Butch Wilmore and Suni Williams are set to splash down on Earth on Tuesday evening after spending more than nine months in space.