Supersonic Aircraft’s Shockwaves Shot by NASA

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 …