What device did Hubble develop for studying bombs and low-velocity projectiles in flight?

Edwin Hubble developed a high-speed clock camera for studying bombs and low-velocity projectiles in flight.

Hubble worked during World War II at the U.S. Army’s Ballistic Research Laboratory at Aberdeen Proving Ground in Maryland. He served as chief of its External Ballistics Branch, applying his scientific skills to military problems rather than astronomical observation.

The camera was part of the instrumentation used in exterior ballistics, the study of how projectiles move through air. By recording rapid events and the motion of bombs or projectiles, it helped researchers analyze flight characteristics and improve weapon design, performance, and effectiveness.

The device is easy to confuse with radar or a general-purpose high-speed camera, but the historical description specifically identifies it as a “high-speed clock camera.” Hubble’s wartime work earned him the Legion of Merit, while his better-known astronomical achievements included demonstrating that galaxies exist beyond the Milky Way and confirming the universe’s expansion.