EDIT: This is delicate. The thread was started in S&D, but just now moved to GD. In no way did I intend to further a conspiracy wing nut theory. I belive there to be a plausible explanation, I just would like to know what it might be: [/EDIT] I saw last night a portion of a conspiracy theory on the 9/11 attacks. Most of it was rather absurd but I could not think of a good explanation for the following. Tapes of the planes hitting the WTC towers clearly show a flash of light just as the nose of the plane touches the side of the building. Four views of the second strike, and the one and only film capture of the first strike show this flash. The conspiracy guy suggested it was an incendiary device to make sure that the fuel ignited upon impact. This suggestion made me snarf my Orangina. But still, what would have caused this flash of light?