Some animals, like the common basilisk (a.k.a. the Jesus Christ lizard) are capable of running across water for short distances. The basilisk accomplishes this feat by slapping the water with sufficient force and speed to keep its body above the surface. This slap also creates a pocket of air around its foot. The lizard propels itself forward by kicking its leg back, then lifting its foot out of the water before the air bubble collapses. Water birds like the Western Grebe and tail-walking dolphins rely on similar physics to stay above the water line. # (submitted by Simon H)
Month: June 2011
Space Shuttle Flow Viz
When a space shuttle lands, a lucky few will hear twin sonic booms as it passes overhead. The double boom occurs due to the shock waves from in front of the shuttle and just behind it passing the observer on the ground. The colorized schlieren photograph above shows shock waves on a model of an early shuttle prototype. The fore and aft shocks that run from the craft to the ground are even clearer on this photo of a T-38 in flight. (Photo credit: Gary Settles)
