Solid Rocket Booster Separation

Rocket in the night sky.
A United Launch Alliance Atlas V rocket launches on the Department of Defense’s Space Test Program 3 (STP-3) mission from Space Launch Complex 41 at Cape Canaveral Space Force Station, Tuesday, Dec. 7, 2021, from NASA’s Kennedy Space Center in Florida. The mission’s Space Test Program Satellite-6 (STPSat-6) spacecraft hosts NASA’s Laser Communications Relay Demonstration (LCRD) and the NASA-U.S. Naval Research Laboratory Ultraviolet Spectro-Coronagraph (UVSC) Pathfinder. Photo credit: NASA/Joel Kowsky

The United Launch Alliance (ULA) Atlas V 551 rocket has jettisoned its five solid rocket boosters and is approaching payload fairing jettison.

At this point in its ascent, the Atlas V is burning propellant at a rate of 2,000 pounds per second, traveling more than 7,500 miles per hour and located 64 miles in altitude and 150 miles down range.

Main engine cutoff will occur about a minute after booster jettison, followed shortly by Atlas Centaur separation.