NASA astronauts Butch Wilmore and Suni Williams are still stranded aboard the International Space Station, and plans for their return trip to Earth are becoming increasingly complicated.
The pair had set off aboard Boeing's Starliner in June for what was supposed to be an eight-day test mission. But the spacecraft, which was delayed and plagued by problems even before liftoff, ran into several problems during its flight, which caused engineers to delay the mission to bring them back.
Now NASA has said it is still not sure the Starliner will be able to return the crew safely as planned. Instead, they may have to return home in February, taking a trip on a SpaceX spacecraft.
NASA has emphasized that the astronauts are not stranded without a solution, in the event of an emergency aboard the space station, they will be able to return home, for example.

Boeing still hopes the problems with the Starliner will be resolved. "We still believe in the Starliner's capability and its flight rationale," the company said.
And NASA says it is working with the company "to assess the readiness of the spacecraft and no decision has been made regarding the return of the Starliner." That decision may not be made until August.
Boeing has said that, if the astronauts must return home on another flight, then it will "take the necessary actions to configure the Starliner for an uncrewed return." This will involve reconfiguring the software so that the Starliner is able to return to Earth without a crew.
This needs to be done because the docking port to be used by SpaceX's next ship needs to be freed.
This likely means that at least most of the spacecraft will burn up upon its entry to Earth. This has always been the plan and is one of the reasons for the delay, engineers will lose most of the spacecraft on its journey through the atmosphere, so they want more time to better understand what might have gone wrong with to.