Schlieren Steak

Schlieren photography of a a steak in a wind tunnel. But you can't tell it's a steak, it's a black silhouette on a dark grey backdrop, with a lens/parabola-shaped shockwave extending from it.

What if What If was real? Randall Munroe back at it again with a Krispy Steak:

I was contacted by Tom Fisher and Thomas Rees, University of Manchester researchers studying hypersonic heat transfer. They had finished their wind tunnel experiments early, so they decided to head to the corner store, buy a steak, and gather some data.

Video 1: A Sainsbury’s 21 day matured beef steak in Mach 5 winds, recorded using Schlieren imaging to show the hypersonic shockwave

Photo source: screenshot from XKCD twitter.