RS-25 engines powering NASA's SLS (Space Launch System) rocket use liquid oxygen and liquid hydrogen as propellants – the same elements that combine to create water (H2O). For an RS-25 engine test, liquid hydrogen and liquid oxygen are mixed in the engine combustion chamber and ignited, which results in extremely high-temperature exhaust (up to 6,000 degrees F) exiting the nozzle into the flame deflector at a very high rate and pressure. Hundreds of thousands of gallons of water also are flowing

Earlier this month, NASA engineers loaded the final test article for NASA's Space Launch System into its test stand at #NASAMarshall! The liquid oxygen tank structural test article, one of two propellant tanks in the SLS core stage, will be pushed and pulled by 38 hydraulic cylinders with millions of pounds of force. Learn more about how we're testing SLS to send Artemis 1 to the Moon >> go.nasa.gov/2XyrEWB | NASA's Marshall Space Flight Center