HANCOCK COUNTY, Miss. (WJTV) – On Wednesday, NASA completed its final test firing of the newly modified RS-25 engines at the Stennis Space Center in Mississippi. The engines will play a key role in the agency’s Artemis missions to the Moon.

“When it tests, it’s operating on its own, its onboard power, onboard control system. It has its own propellants on board, obviously. And so, the facility is hands-off. And so, we aimed to test it exactly like it’s intended to fly,” explained Ryan Roberts, NASA test director at the Stennis Space Center.

Operators fired the engine for 500 seconds, which is the time needed to launch a Space Launch System (SLS) rocket. The engine power levels reached 113%.

NASA will evaluate the performance of new engine components, including a nozzle, main combustion chamber, and engine controllers.

“Once we find how this system acts upon the thermodynamics, the acoustic dynamics, the pressures, the everything about these systems, and once we know that system, we can lock down a design,” said Michael McDaniel, with Aerojet Rocketdyne.

Officials with Stennis’ Operations Division said the test appeared successful because they did not see any initial issues. The engines will be used to power the SLS rocker on future Artemis missions to the Moon and Mars, beginning with the Artemis 5.

More data from the test will be collected before full engine production is approved.