According to NASA, Crew-9 is scheduled for launch no earlier than 1:17 p.m. on Saturday, September, on a SpaceX Crew Dragon.

It will have just two astronauts on board: Commander Nick Hague, a U.S. Space Force Guardian, and cosmonaut Aleksandr Gorbunov. You can watch it on NASA’s YouTube channel, on NASA+, or on NASA’s website.

Typically, ISS rotation crews are four astronauts, but this launch is unique. Two astronauts, Zena Cardman and Stephanie Wilson, were pulled off the flight to make room for Butch Wilmore and Suni Williams. These Boeing Starliner astronauts, whom NASA insists aren’t stranded on the ISS, need a new ride.

As a result, this flight has been delayed—it was initially scheduled for mid-August, but NASA delayed the launch when the Boeing Starliner management team realized they’d need more time to decide how to bring those astronauts home. It was rescheduled for September 24, then delayed to September 26, and now September 28. This is the first crewed launch from Launch Complex 40, and presumably, NASA needed more time to put the necessary launch infrastructure in place.

No immediate danger, but plenty of drama

Across fiction and nonfiction, space rescue missions have a rich history. NASA has often had contingency plans in the works for crewed spaceflight—modifying an Apollo capsule to potentially rescue stranded crews from the Skylab space station, keeping a Space Shuttle on the launch pad in case a risky final servicing mission for Hubble went awry. But it’s not often in history that these rescue spaceships launch—and that’s what we’re facing this week.

This isn’t a rescue in the traditional sense; Wilmore and Williams aren’t in danger, but the rule on the ISS is that any astronauts on board must have a way off the Space Station. Because Boeing Starliner undocked on September 6, right now, their only way home is a contingency plan that would see them as two extra astronauts on Crew-8 in makeshift seats strapped down to the cargo area. (Note that the ISS has been continuously occupied since 2000 and has never been evacuated, so it’s unlikely we’ll see this scenario in action.)

Once Crew-9 arrives at the ISS, Wilmore and Williams will assume the duties of the two remaining astronauts for the duration of the five-month mission. They are scheduled to return in February 2025, turning what was supposed to be an eight-day test flight into an eight-month-long stay aboard the ISS.