The SpaceX Crew-9 mission is heading toward the International Space Station to join Starliner astronauts

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After turning their week-long trip into a month-long stay on the International Space Station, two Boeing Starliner astronauts will soon be reunited with the spacecraft that will eventually bring them home.

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

NASA astronaut Nick Hague and Russian cosmonaut Alexander Gorbunov are on board the SpaceX spacecraft. Next to them are two empty seats, saved for Williams and Wilmore to occupy when the group returns to Earth next year.

Hague and Gorbunov lifted off aboard the Crew Dragon spacecraft Saturday afternoon from Cape Canaveral Space Force Station in Florida. Although they reached their intended orbit without a hitch, SpaceX later revealed that the second stage, or upper section, of the Falcon 9 rocket that powered the first part of their flight had a problem after it separated from the capsule.

“Following today’s successful launch of Crew-9, the Falcon 9 second stage was jettisoned into the ocean as planned, but experienced an indefinite deorbital burn,” the company shared in a statement. Share on Xthe social media platform formerly known as Twitter. “As a result, the second stage landed safely in the ocean, but outside the target area.”

SpaceX has indicated that it will temporarily halt flights using the Falcon 9 – the world’s fastest-flying rocket – while it explores the anomaly. “We will resume the launch after we better understand the root cause,” the company said in the X post.

CNN has reached out to the FAA for comment.

Meanwhile, Crew-9’s Crew Dragon capsule spent about a day traveling through orbit While preparing to dock with the International Space Station. Once the spacecraft is safely attached to one of the station’s docking ports, it will open its door, allowing Haag and Gorbunov to join the other astronauts already aboard the orbiting laboratory.

Together, Hague, Williams, Willmore and Gorbunov will complete SpaceX’s Crew-9 team. The group will spend about five months aboard the space station before returning home no later than February.

Williams and Willmore first traveled to the International Space Station in early June aboard a Boeing Starliner spacecraft in what was expected to be a week-long test mission.

But problems with helium leaks and faulty thrusters left engineers scrambling to figure out what went wrong — and NASA ultimately decided that the Starliner’s problems weren’t well understood enough for the space agency to allow Williams and Willmore back on board.

Instead, the Starliner flew home empty on September 6.

After deciding not to return Williams and Wilmore to Earth aboard the Starliner ship, NASA instead chose to rearrange SpaceX’s flight plans, kicking out two more astronauts — spaceflight veteran Stephanie Wilson and Zina Cardman, who was about to make her maiden flight to Earth. Space – from the crew. -9 Mission to make room for the Starliner team.

But this means that Williams and Willmore will have to fulfill the duties of the original Crew-9 crew, as they will take months of routine work on the space station before the return trip.

Both Williams and Willmore – veterans of previous missions to the International Space Station – said they have easily adjusted to the idea of ​​staying in space until next year, with Williams noting that the microgravity environment is her “happy place.”

The crew currently aboard the International Space Station includes Don Pettit, Alexei Ovchinin of NASA, and Ivan Vagner of the Russian space agency Roscosmos. The three arrived at the space station aboard a Russian Soyuz spacecraft on September 11.

Pettit and Gorbunov rode aboard a spacecraft developed outside their home countries as part of a seat-swap agreement between NASA and its Russian counterpart.