This is the launch timeline to be followed by the Atlas 5 rocket’s ascent into orbit from Cape Canaveral with the SBIRS GEO Flight 3 satellite for U.S. military infrared reconnaissance. Launch is scheduled for Thursday at 7:46 p.m. EST (0046 GMT).
When the next Delta 4 rocket flies in July, as well as all future ones to come, the enhanced RS-68A main engine will power the boosters off the launch pad.
The last flight of United Launch Alliance’s Delta 4-Medium rocket lifted off Aug. 22 from Cape Canaveral Air Force Station in Florida, riding more than 1.2 million pounds of thrust from a hydrogen-fueled main engine and two strap-on solid rocket motors.