Photos: Atlas 5 on the pad at sundown

The step-by-step stacking of United Launch Alliance’s final Delta 2 rocket was completed in June at Vandenberg Air Force Base in California for liftoff Sept. 15 with an Earth science satellite for NASA.

United Launch Alliance’s Atlas 5 rocket made its way back to the pad at Space Launch Complex 41 at Cape Canaveral Space Force Station on Thursday morning for a mission carrying national security mission payloads, collectively codenamed Silentbarker. Liftoff has been rescheduled for at 8:47 a.m. EDT (1247 UTC).

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.