The Space Launch System (SLS) is NASA's next generation heavy-lift rocket, the powerful vehicle to get us to Mars, back to the moon, to an asteroid, or even to Europa. But first, of course, it has to get off Earth. Thursday at 5 p.m., NASA will take another big step in that quest, test firing the RS-25 engine.
The fundamentals of the RS-25 were used for decades on the Space Shuttle program, though the SLS model includes new controllers to regulate thrust and fuel, as well as providing an analytical overview of everything happening in the engine. This is the second-to-last RS-25 test, which most recently ran in January and June. In March, NASA also tested the QM-1 motor, the five-segment solid-fuel booster rockets that help the heavy-weight SLS lift off of Earth. It is "the Ferarri of rocket engines," if you ask NASA.
NASA-TV has had a full slate of coverage today, as well as the actual fire test, with commentary starting at 4:30 p.m. for a 5 p.m. "launch." The test will last roughly nine minutes in total. You can watch the test in the player below: