November - Assembly of the world's first general purpose electronic computer, the Electronic Numerical Integrator Analyzer and Computer (ENIAC), is completed. It covers 1800 feet of floor space. The first set of calculations is run on the computer.
Meteorology
High-altitude west-to-east winds across Pacific, discovered by Japanese in 1942 and by Americans in 1944, are dubbed "jet stream"
August 11 – Smyth Report released by U.S. government, informing the public of the basics of nuclear fission and its military and civilian applications. Emphasizes the role played by physics in the development of the atomic bomb.