Live video of launch pad 39A (members only)

NASA astronauts Bob Behnken and Doug Hurley will be geared up for the long haul when they launch from the Kennedy Space Center on a SpaceX Crew Dragon spacecraft later this month, but they won’t know exactly how long they will be in orbit until they are already aboard the International Space Station.

The Falcon 9 booster for SpaceX’s next mission fired up briefly on a Cape Canaveral launch pad Sunday in a routine pre-flight test before a scheduled launch Friday night to kick off the final flight of the first version of the company’s Dragon cargo capsule to the International Space Station.

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.