Science Art: Schlieren photograph of a T-38 at Mach 1.1, altitude 13,700 feet, by Leonard Weinstein.

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This is what a sonic boom looks like, through a Schlieren camera – one outfitted to see differences in air pressure. The T-38 pilot could probably feel these bands of pressure through the yoke and the wings – but they’re invisible to human eyes.

Image from NASA’s Dryden Flight Research Laboratory.