If you dabble in NASA news, you've probably heard of the agency's main space centers: Johnson (the "Houston, we have a problem" one) and Kennedy (the Cape Canaveral launch site one). Today, though, all eyes were on the lesser-known Stennis Space Center in Hancock County, Mississippi, where NASA completed one of the last tests of an engine that will help to propel its Orion crew capsule on future deep-space missions—maybe even a manned mission to Mars.

When the Space Launch System sends the Orion spacecraft into orbit, its first stage will be powered by four RS-25 engines, an old design used as the main engine for NASA's shuttle program. But the engine has undergone a number of changes to work with the SLS, including designs to deal with higher propellant inlet pressure, lower temperatures, and a new engine controller unit. This was the sixth of seven planned static fire tests of the updated engine.

Today's test at NASA's largest rocket engine testing facility mimicked a full launch, firing the engine's 512,000 pounds of thrust for a straight 535 seconds, the time it would take to climb 200 miles. It burned a combination of liquid oxygen and liquid hydrogen, releasing its exhaust in a massive plume of steam out of one side of the test stand—along with all the energy that typically would got into, you know, actually launching the thing. Onlookers watching from a safe distance got nearly nine minutes of bone-rattling power. Keep an eye out for the last planned engine test for the RS-25.