*Delta IV-Heavy Launch Klaxon*

Coming up on 60 minutes to the launch of NROL-71 or ULA's big rocket.

Extensive Preview Article:https://t.co/p39Nm4wv0l - by William Graham

Play by Play Updates:https://t.co/JNCNqgKYIx

WEBCAST: https://t.co/8lhLtBXZYc

— Chris B - NSF (@NASASpaceflight) December 9, 2018