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Science

NASA Tests RS-25 Engine No. 10001 at Stennis Space Center

NASA teams conducted a hot fire test on RS-25 engine No. 10001 at the Stennis Space Center on October 21, 2026. The test, which lasted almost eight-and-a-half minutes (500 seconds) at 111% power, allows NASA and L3Harris Technologies to gather data to enhance engine performance and dependability.

Assembled News Desk1 min read
AI illustration based on reference photographs; not an event photograph. A large engine test stand structure with a massive plume of white smoke billowing against a bright sky, set near water and green foliage.
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On October 21, 2026, personnel at NASA’s Stennis Space Center, located near Bay St. Louis, Mississippi, conducted a test of RS-25 engine No. 10001. According to NASA News Releases, this hot fire test lasted for nearly eight-and-a-half minutes, which equates to 500 seconds. This duration mirrors the time RS-25 engines operate during the launch of NASA’s Space Launch System (SLS) rocket, and the test was conducted at a 111% power level.

For the purpose of each Artemis mission, four RS-25 engines generate a combined thrust of up to 2 million pounds to assist in launching the SLS rocket. NASA News Releases stated that all RS-25 engines are verified as flightworthy at NASA Stennis before they are put into service.

Although the engine tested during this event is a developmental unit and will not be utilized in a flight, the hot fire test offers NASA and its primary engine contractor, L3Harris Technologies, the opportunity to collect essential data to enhance the engine's reliability and performance.

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