NASA Successfully Test Fires J-2X Engine.
tetrahedrassface writes "NASA successfully test fired the J-2X engine Wednesday for 500 seconds at Stennis Space Center. The J2-X is derived from the J2 engine from the Apollo Era, and will power the upper stage of the SLS. From the article: 'We have 500 seconds of good data, and the first look is that everything went great. The J-2X engine team and the SLS program as a whole are extremely happy that we accomplished a good, safe and successful test today,' said Mike Kynard, Space Launch System Engines Element Manager at NASA's Marshall Space Flight Center in Huntsville, Ala. 'This engine test firing gives us critical data to move forward in the engine's development.'"
The article says the J2-X uses liquid oxygen and liquid hydrogen as fuel. Does that imply the byproduct of the J2-X is water vapor? The old Apollo rockets used kerosene. I know NASA used a lot of water to control heat and vibration for shuttle launches and other rocket tests (which is likely what you see in the video)... but is that also the exhaust gas here?
Most of the white stuff you see in the video is steam from cooling and sound supression systems. But, in EVERY combustion in air, even if burning pure hydrogen and oxygen, there is some amount of nitrous oxides produced from the nitrogen present in air. This is an inescapable fact of chemistry. But what you're seeing is water vapor.
Chaos maximizes locally around me.
Mist, actually. Steam, which is water in its gas state, is invisible. The bit that you can see is actually an aerosol of water in its liquid state.
The mixture is often referred to as "wet steam", but it's the wet bit that you can see, not the steam bit.
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