Comment on Apollo Moon Landing Hoax – Scientific Evidence by jfb.

Apollo Moon Landing Hoax - Scientific EvidenceFlame in rocket exhuast varies depending on ambient pressure and fuel type.

Go to SpaceX’s web site (http://www.spacex.com) and check out the launch videos for the Falcon 9. As the booster ascends into the upper atmosphere, the ambient pressure drops and the exhause plume expands dramatically and becomes much less flamey; by the time the first stage shuts down, the exhaust plume is several times wider than the stage and there’s almost no visible flame. When the second stage lights, you see very little flame at the edges of the engine bell. Both of those stages use RP-1 (kerosene) for fuel and liquid oxygen for the oxidizer, so they burn a little “dirty” and there are a lot of particulates in the exhaust (the smoke).

The engines on the LM used aerozine 50 as the fuel and nitrogen tetroxide as the oxidizer, which burn relatively clean, which can sort of be seen in the image below:

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=24404

And again, since the engine is burning in a vacuum, the exhaust plume expands immediately, so you don’t get any visible flame. I don’t remember offhand if its the video for 15 or 16, but one of them shows plenty of dust and debris being kicked up when the ascent stage clears the descent stage platform.