A ring of water vapor begins to form as pilots Lt. Justin Halligan (L) and Lt. Michael Witt (R) fly their F/A-18F Super Hornet airplane within 200mph of breaking the sound barrier while performing at New York Air Show at Jones Beach in Wantagh, New York, May 23, 2009. The phenomenon is created when the plane, travelling at low altitudes over water, approaches the speed of sound and the pressure created by the forward sound waves squeezes moisture in the air to form a ball of cloud over the front of the aircraft. (2 of 11) REUTERS/Christopher Pasatieri (UNITED STATES TRANSPORT MILITARY SCI TECH)