That’s how long Boeing Starliner’s mission — its first flight test with crew aboard — was supposed to last. But this mission has been singular in almost every way, and astronauts Butch Wilmore and Suni Williams have instead spent the past nine and a half months aboard the International Space Station.

The astronauts were planning to come back on Wednesday but "favourable" weather conditions meant their return could be brought forward by one day, according to NASA.