Video: NROL-37 payload and Delta 4-Heavy rocket prepped for launch

Gearing up for a predawn blastoff July 31, launch crews have positioned a Delta 4-Heavy rocket in the starting blocks on a seaside launch complex at Cape Canaveral as engineers inside a tightly-controlled clean room a few miles away put the final touches on a NASA probe that will travel closer to the sun than any mission before.

An Atlas 5 rocket lifts off from launch complex 41 at Cape Canaveral carrying the SBIRS GEO-4 missile early warning satellite in this video shot from the Kennedy Space Center Press Site.

NASA managers Thursday cleared the $1.5 billion Parker Solar Probe for launch early Saturday on a daring mission to “touch the sun,” repeatedly flying through its outer atmosphere to find out why the blazing corona is millions of degrees hotter than our star’s visible surface.