SpaceX Crew 9 Flight and Butch and Sunni's ride home

Crew-9, the ninth operational SpaceX astronaut flight to the International Space Station (ISS) for NASA, is scheduled to lift off from Florida's Cape Canaveral Space Force Station today at 1:17 pm EDT (1717 GMT).

The two astronauts on board are commander Nick Hague, who is with NASA and the U.S. Space Force, and mission specialist Aleksandr Gorbunov, of the Russian space agency Roscosmos.

Assuming today's launch goes on time, Hague and Gorbunov are scheduled to dock with the ISS on Sunday (Sept. 29) at 5:30 p.m. EDT (2230 GMT), with coverage starting on NASA+ two hours beforehand. The hatch opening between the station and Dragon will occur at roughly 7:15 p.m. EDT (2315 GMT).

Related: SpaceX's Crew-9 astronaut flight for NASA launches this week. Here's how it turned into a rescue mission

SpaceX Crew Dragon capsules usually carry four people to the ISS on such missions. But Crew-9 is leaving two seats empty so the Dragon can bring home two NASA astronauts — Butch Wilmore and Suni Williams — who reached the orbiting lab in June, on the first-ever crewed mission of Boeing's Starliner capsule. Starliner returned to Earth uncrewed on Sept. 7, however, after suffering thruster problems in orbit.