In 1951, Jay Forrester applied for a patent for magnetic core memory.
Until then, large glass electrostatic tubes were used. They were very unreliable, failing every twenty to sixty minutes. Forrester began a search for reliable memory capability. This would lead him to make one of the most important discoveries in computer history: magnetic-core memory.
In 1916, German astronomer Karl Schwarzschild died.
Schwarzschild predicted the existence of black holes. He also established a method for determining a star’s brightness from photographs by comparing its visual and photographic magnitudes to other stars to obtain their color index.