Clouds of white vapor pile up at NASA’s Stennis Space Center in Bay St. Louis, Mississippi, during a full-duration, 500-second hot fire of an RS-25 certification engine Jan. 17, 2024. This test series is critical for future flights of NASA’s SLS (Space Launch System) rocket in support of the Artemis campaign.

During the Jan. 17 test, operators followed a “test like you fly” approach, firing the engine for the same amount of time – almost eight-and-a-half minutes (500 seconds) – needed to launch SLS and at power levels ranging between 80% to 113%.

Image Credit: NASA/Danny Nowlin