Hot Fire! NASA Tests Powerful Artemis Moon Rocket Engine

NASA fired up an RS-25 rocket engine at Stennis Space Center in Mississippi on Oct. 21, 2026. It was a hot-fire test of developmental RS-25 engine No. 10001. The test was planned to last 500 seconds (8 minutes, 20 seconds), with the engine reaching up to 111% of its rated power level. The firing is part of ongoing testing to support NASA's Space Launch System (SLS) rocket, which will carry astronauts toward the moon on future Artemis missions. Four RS-25 engines power the core stage of each SLS rocket. Credit: NASA | edited by Space.com