United States astronauts Doug Hurley and Bob Behnken have undocked their Dragon Endeavour pill from the spaceport station to start their go back to Earth.
The set are anticipated to splash down off the coast of Florida simply after 14: 45 EDT (19: 45 BST) on Sunday.
A successful landing would mean America as soon as again has a totally serviceable, fully licensed means of getting its own people into orbit and back.
This capability was lost when the nation retired its shuttles in 2011.
The United States area firm Nasa and its commercial partner, SpaceX, have selected a splashdown location well away from Cyclone Isaias, which looks as though it will track up the eastern coast of Florida.
Waiting recovery vessels are therefore being directed to the Gulf of Mexico, to waters off Pensacola in western Florida.
Mission controllers are following stringent guidelines on acceptable wind and wave conditions, and will study the current projections prior to offering a last “go” for re-entry.
When that takes place, Hurley’s and Behnken’s pill will light its thrusters to start the drop out of orbit.
It’s a high-speed descent, at first at a number of kilometres per 2nd, and will see Endeavour experience heating of up 2,000 C on its shielded underside as it pushes down through the environment.
2 sets of parachutes are set to release – a drogue system at about 5,500 m (18,000 feet) in altitude when the pill is still moving at approximate