Live coverage: Delta 4-Heavy rocket launches from California

Live coverage of the countdown and launch of a Delta 4-Heavy rocket with the classified NROL-91 payload for the National Reconnaissance Office. Text updates will appear automatically below. Follow us on Twitter.

ULA broadcast

United Launch Alliance’s live launch broadcast begins at 2:33 p.m. PDT (5:33 p.m. EDT; 2133 GMT) on Saturday, Sept. 24.