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Watch NASA test fire a giant rocket engine for its mighty Space Launch System

When most rocket engines fire up, they’re going places. But not the RS-25.

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NASA this week anchored its RS-25 booster engine — one of four for its Space Launch System (SLS) rocket — firmly to the ground for a spectacular test that powered it to a 113-percent thrust level for a full 50 seconds. This was its highest level to date following several similar test fires.

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Footage captured from cameras placed around the test site at Stennis Space Center in Mississippi show the engine’s awesome power as it fills the surrounding area with a mass of condensing water vapor and enough noise to wake the neighbors.

The RS-25 engines were used in the space shuttle program that ended in 2011, and have been modified to supply the added power needed for the larger, heavier SLS rocket. It’s one of the most heavily tested large rocket engines ever, according to NASA, with more than 3,000 starts and more than a million seconds of total ground test and flight firing time.

Four RS-25 engines will provide a combined two million pounds of thrust for the first SLS launch, expected in 2019, but with a pair of additional solid rocket boosters this increases to a phenomenal 8 million pounds. To give that some context, SpaceX’s Falcon Heavy boosters generated around 5 million pounds of thrust when it launched earlier this month.

The SLS will be the most powerful rocket in the world when it goes into operation, beating the Saturn V that took astronauts to the moon before the rocket was retired in 1973.

NASA’s SLS Exploration Mission-1 (EM-1), planned for next year, will serve as the maiden flight for the new rocket and deploy an uncrewed Orion spacecraft in low-Earth orbit to test out the performance of the integrated system.

“As the SLS evolves, it will provide an unprecedented lift capability … to enable missions even farther into our solar system,” NASA said.

Looking further ahead, the EM-2 flight, scheduled for 2022 if everything goes to plan, will for the first time carry a crew of astronauts aboard Orion. The mission could include a trip around the moon lasting up to three weeks and involve delivery of parts for a new space station to aid deep space exploration.

Trevor Mogg
Contributing Editor
Not so many moons ago, Trevor moved from one tea-loving island nation that drives on the left (Britain) to another (Japan)…
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