STS-135: The final space shuttle landing

SpaceX has pushed back the liftoff of a Bulgarian television broadcast satellite on the company’s second previously-flown Falcon 9 rocket until at least Friday, giving ground crews time to replace a valve on the launcher inside a hangar at its Florida launch pad.

A Falcon 9 booster that flew into space last year is set to launch again Thursday from Florida’s Space Coast with an SES communications satellite on a historic mission that could make major strides in validating SpaceX’s audacious goal of recovering and reusing launchers, an achievement the company says will revolutionize the rocket business. Liftoff is set for 6:27 p.m. EDT (2227 GMT).

SpaceX has moved up its next launch to Wednesday, one day earlier than previously planned. A Falcon 9 rocket will take off with the next 60 satellites for SpaceX’s Starlink broadband Internet network at 3:37 p.m. EDT (1937 GMT) Wednesday from pad 39A at NASA’s Kennedy Space Center in Florida. There’s a 90 percent chance of favorable weather for launch Wednesday.