Four astronauts headed to the International Space Station on Sunday, where they will oversee the arrival of two new rocketships during their half-year stint.

SpaceX’s Falcon rocket blasted off from Kennedy Space Center, carrying Nasa’s Matthew Dominick, Michael Barratt, Jeanette Epps, and Russia’s Alexander Grebenkin.

The astronauts should reach the orbiting lab on Tuesday.

They will replace a crew from the US, Denmark, Japan and Russia, who have been there since August.

“When are you getting here already?” space station commander Andreas Mogensen asked via X, formerly Twitter, after three days of delay due to high wind.

There was almost another postponement on Sunday night.

SpaceX Crew Launch
A SpaceX Falcon 9 rocket and Dragon capsule with a crew of four on a mission to the International Space Station lifts off from pad 39A at the Kennedy Space Center (John Raoux/AP)

A small crack in the seal of the SpaceX capsule’s hatch prompted a last-minute flurry of reviews, but it was deemed safe for the whole mission.

The new crew’s six month stay includes the arrival of two other rocketships ordered by Nasa.

Boeing’s new Starliner capsule with test pilots is due in late April.

Sierra Space’s Dream Chaser, a mini-shuttle, should arrive a month or two later.

It is for delivering cargo to the station, but not passengers.