Starliner astronauts' replacement crew arrive at International Space Station

Just over a day after blasting off, a SpaceX crew capsule arrived at the International Space Station on Sunday, delivering the replacements for NASA's two stuck astronauts.

The four newcomers — representing the U.S., Japan and Russia — will spend the next few days learning the station's ins and outs from Butch Wilmore and Suni Williams. Then the two will strap into their own SpaceX capsule later this week, one that has been up there since last year, to close out an unexpected extended mission that began last June.

Wilmore and Williams expected to be gone just a week when they launched on Boeing's first astronaut flight. They hit the nine-month mark earlier this month.