The first-ever images of two shockwaves interacting, taken by NASA, appeared online this week. These photos—shot using a 150-year-old German technique—are some of the first of supersonic flights in the air and not in a wind tunnel. Seeing how the shockwaves interact with one another and on their own, NASA may be able to reduce the noisiness of sonic booms—the result of pressure changes when an aircraft breaks the sound barrier. The shots are mesmerizing, too. See more at Fortune.