NASA teams carried out a critical test of the Space Launch System (SLS) core stage at Stennis Space Center. All four RS-25 engines ignited successfully during the Green Run hot fire test, a major milestone on the path to the Artemis I Moon mission. Although the firing ended early, the onboard flight software performed exactly as designed and safely shut down the engines. Engineers gathered valuable data as the massive propellant tanks were pressurized, helping prepare the most powerful rocket ev