NASA engineers placed the engine inside a massive test stand at the Stennis Space Center in Mississippi and test-fired the third of four engines that will ultimately lift the first SLS rocket into space. The engine blasted the ground for 500 seconds, the expected time that it would need to reach Earth’s atmosphere.
Earlier versions of the RS-25 engines proved their worth over three decades by providing the thrust for space shuttles until their retirement in 2011. While the shuttles used three of these rockets, the four-rocket configuration on the SLS rocket, in combination with two more rocket boosters attached to the side of the rocket, means the entire system will produce 8.8 million pounds of thrust, making it “the most powerful rocket in the world,” according to NASA.
The super-heated gases leave the engine nozzles at 13 times the speed of sound. Liquid hydrogen meets liquid oxygen in the combustion chamber above the nozzle, producing the tremendous exhaust velocity shown above.
The SLS’s first test flight isn’t slated until 2019, so it hasn’t received as much attention as SpaceX’s Falcon 9, which is powered by nine SpaceX-produced Merlin engines, each producing about 190,000 pounds of thrust. The Falcon 9 has already flown nine successful missions this year, with a host more on the docket. In most instances, the Falcon 9 also descends from space and lands on a drone platform in the middle of either the Atlantic or Pacific Ocean, producing a double-whammy of media attention.
But with powerful 500-second test blasts like this, NASA reminds the space community that it is still very much in the rocket game, and has every intention of sending its own crewed mission to Mars.