October 13

On October 13, 1892, American astronomer Edward Emerson Barnard achieved a milestone by locating a comet through photographic plates. Previously, comets had been spotted only by direct telescopic observation. Barnard's use of photography revolutionized the detection and study of celestial objects. His method allowed for precise recording and analysis of faint astronomical bodies. This breakthrough paved the way for modern astrophotography and automated sky surveys. Barnard’s discovery cemented his reputation as one of the leading observational astronomers of his time.

On October 13, 1976, Dr. F. A. Murphy at the Centers for Disease Control and Prevention captured the first electron micrograph image of the Ebola virus. This breakthrough provided virologists with the first detailed look at the morphology of one of the world's most deadly pathogens. The image revealed the characteristic filamentous shape of the virus particles. Researchers could now study the virus structure to inform diagnostic tests and vaccine development. This milestone advanced the scientific understanding of viral hemorrhagic fevers and underscored the importance of advanced microscopy in infectious disease research.

On October 13, 1983, Ameritech Mobile Communications activated the first commercial cellular telephone network in Chicago, marking the dawn of widespread mobile communication in the United States. The network began with service to the city and its suburbs, allowing users to make calls without landlines. This milestone came five years after initial experiments and regulatory approval for cellular service. Early subscribers paid hefty fees and used bulky handsets, but the convenience factor drove rapid adoption. The Chicago launch paved the way for nationwide network expansion and the mobile revolution. It changed how people stayed connected and laid the foundations for the smartphone era.