For all the space junkies out there: The first flight test of Orion, NASA's next-generation spacecraft capable of sending astronauts on future missions to an asteroid and the journey to Mars, has been rescheduled.

The launch is now is scheduled to launch at 7:05 a.m. EST Friday, atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida. There is a two-hour, 39-minute window for the launch.

A Thursday launch attempt was scrubbed because valve issues could not be remedied before the launch window closed, officials said. Several valves are used to fill and drain the first stage of the rocket with propellant before liftoff.

The flight is expected to last about 4½ hours, with a splash down in the Pacific Ocean about 600 miles southwest of San Diego. During its trip, designated Exploration Flight Test-1, Orion is to orbit Earth twice and travel 3,600 miles into space.

The flight is designed to test many of the most vital elements for deep-space human spaceflight and will provide critical data needed to improve Orion's design and reduce risks to future mission crews.

It is NASA's first craft designed for manned missions to fly since its final space shuttle, Atlantis, landed on July 21, 2011, at Kennedy Space Center in Florida.