Photos: Atlas 5 rolls out for launch

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).

Hoisting a 15,000-pound satellite atop an Atlas 5 rocket Wednesday, United Launch Alliance finished assembling its next space-bound booster for liftoff Aug. 31 in support of the U.S. Navy.

Student-built miniature satellites to demonstrate 3D printing to make repairs in space, a mission to study solar explosions hitting the Earth, a technology test for deorbiting smallsats and a precursor to a commemorative time capsule have won free launches into space aboard Atlas 5 rockets in United Launch Alliance’s first-ever cubesat challenge.