Video: Weather causes Atlas 5 countdown hold

NASA’s Parker Solar Probe, fueled and buttoned up for liftoff Aug. 11 on the first mission to fly through the sun’s corona, arrived at its launch pad at Cape Canaveral early Tuesday after a convoy trip from a nearby fueling and test facility.

The Air Force’s miniature space shuttle and its ride to orbit have been joined together inside an assembly building at Cape Canaveral in preparation for launch May 20.

NASA managers say the WFIRST mission, the next in the agency’s line of powerful observatories after the Hubble and James Webb telescopes, could cost around $3.2 billion after budgeting for a novel first-of-its-kind instrument to probe the make-up of planets around nearby stars and a bigger-than-expected launch vehicle.