ULA's Vulcan Rocket Passes Test-Fire Milestone Ahead of Debut Flight

United Launch Alliance's (ULA) Vulcan Centaur rocket successfully fired its engines during a static fire test, bringing it one step closer to its debut flight. The rocket, which is set to replace ULA's Atlas V and Delta IV rockets, has faced several setbacks, including a delayed response from its booster's engine ignition system and a fiery explosion during a test stand pressurization. The rocket's first mission will attempt to deliver Astrobotic's Peregrine lunar lander and the first two Amazon Kuiper internet satellites. ULA is under contract to deliver 35 missions for the U.S. Space Force in the next five years.