Supersonic

Shockwaves from two T-38 aircraft flying supersonic - NASA

This photo was taken from a Beechcraft King Air that was flying above the T-38's. Since the T-38's were traveling like three times as fast as the Beech, timing was critical.

NASA Beechcraft King Air flying over the giant compass rose at Edwards Air Force Base in California

They did this before using ground based cameras shooting at the sun, which provided a nice collimated light source.


NASA Supersonic Flights Validate Flightworthiness for Future Schlieren Imaging
How they got the most recent image while looking at the ground is a mystery.