Watch the Falcon 9 launch from pad 39A

An unpiloted test flight of Boeing’s Starliner crew capsule to the International Space Station will be delayed from its previous target launch date of April 2 until at least May, after the arrivals of Russian Soyuz and SpaceX Crew Dragon ships bringing fresh crew members to the orbiting complex, NASA officials said Monday.

The European-built Solar Orbiter spacecraft arrived in Florida late Friday after a trans-Atlantic journey from a test center in Germany, ready to begin preparations for a liftoff from Cape Canaveral in February aboard a United Launch Alliance Atlas 5 rocket.

With Hurricane Isaias threatening Florida’s East Coast, astronauts Doug Hurley and Bob Behnken are awaiting a go-ahead on plans to undock from the International Space Station Saturday, setting up a fiery plunge to splashdown Sunday, presumably in the Gulf of Mexico, to close out a 64-day flight.