Moisture!

[redshirt1957]

Originally Posted by R.mojo

really cool pictures, the first boom, is that when he blasts mach 1?

You break the barrier around 750mph. Temperture, and not humidity or pressure, affect the speed at which you will break the sound barrier. You don't always get visable mositure. The driver was going around 770mph I figure. There are two factors that come into play that gives you the boom or sound waves in air......compression and shear stresses. Now, you have made my head hurt.

Remember, air is a fluid.