An oblique shock is a shock wave that, unlike a normal shock, is inclined with respect to the direction of incoming air. It occurs when a supersonic flow encounters a corner that effectively turns the flow into itself and compresses. This photograph shows an oblique shock at the nose of a Northrop T-38 Talon aircraft, made visible through Schlieren photography.
Photograph credit: NASA & US Air Force (J.T. Heineck, Ed Schairer, Maj. Jonathan Orso, Maj. Jeremy Vanderhal)
.jpg)