They're wrong.  Notice the 2 close but distinct stages They also LIED.  That isn't an "infrared" photo.  It's just a doctored photo that someone used MSPaint to invert the colors on.  Woooo 10 year olds 20 years ago making "alien" and "ghost" photos! Huge plume of FUEL, and then the triggered ignition once the fuel was atomized.  Thermobaric / fuel-air bomb. https://www.youtube.com/watch?v=O6gCZuIr14w