NASA test-fired an RS-25 rocket engine today, 08/18/2016, at the Stennis Space Center in Bay St. Louis in Mississippi. The RS-25 is one of four modified space shuttle main engines that will help lift the huge SLS rocket off the ground assisted by two solid rocket boosters.*
The RS-25 engines are fueled by liquid oxygen and liquid hydrogen. Combined, the four RS-25 engines on SLS will generate 2 million pounds of thrust.
Click HERE to watch a test of the solid rocket booster.