Live coverage: Practice countdown completed for Starliner and Atlas 5

A major test of the system that would shoot SpaceX astronaut crews away from a failing rocket is scheduled for no earlier than May 5 from a specially-built mount at Cape Canaveral’s Complex 40 launch pad, NASA announced Tuesday.

SpaceX’s Falcon 9 rocket will go from Cape Canaveral to low Earth orbit in 10 minutes Friday with a Dragon capsule heading for the International Space Station carrying nearly 7,000 pounds of supplies and experiments.

Less than a week after winding up a successful spacewalk, outgoing space station commander Jeff Williams, America’s most experienced astronaut, will join two Russian cosmonauts for a fiery descent to Earth Tuesday evening to close out a 172-day mission covering 2,752 orbits and 72.8 million miles since launch last March.