On this day: March 29

First Confirmed Deaths from Acute Radiation Exposure, March 29, 1945

On March 29, 1945, the first confirmed fatalities attributed to acute ionizing radiation exposure were recorded following a criticality accident at the Los Alamos Laboratory’s Omega Site during the Manhattan Project; the event highlighted unknown risks of handling fissile material and influenced later radiological safety practices.

The Beatles’ Last Public Concert: Candlestick Park, March 29, 1966

On March 29, 1966, The Beatles gave their final official public concert at Candlestick Park in San Francisco, closing a touring era marked by frenzied crowds, short setlists and growing studio focus.

Karl Landsteiner Publishes First Human Blood Type Classification

On March 29, 1901, Austrian immunologist Karl Landsteiner published findings that identified distinct human blood groups (A, B, and O), laying the foundation for safe blood transfusion and modern immunohematology.

Early electric toaster debuts in 1909

On March 29, 1909, the first widely recognized electric toaster—the Waters-Genter snap-action toaster—was introduced, marking a shift from stovetop and long-wire toasting methods toward compact electric household appliances.