The EURion constellation is a pattern of five small yellow, green, or orange circles repeated across areas of a banknote. The technical details of the EURion constellation are top secret, but it is known to help software programs detect a banknote in a digital image so that users cannot produce counterfeit bills. Some programs not only abort attempts to access images of banknotes but also direct the user to a website about counterfeiting laws. What currencies feature the EURion constellation?
Back in the day
The parking meter was invented in 1935 by Carl C. Magee in Oklahoma City, Oklahoma. The first meter was installed there later that year, guaranteeing drivers a parking space for an amount of purchased time. Used until the 1980s, Magee's original design had a coin acceptor, a dial, and a visible flag indicating the expiration of paid time. Reverend C.H. North was the first person in the US to get a parking ticket because of an expired meter. What happened when he disputed his ticket in court?
Born on a day like today
Amundsen was a Norwegian polar explorer who led the first expeditions to traverse the Northwest Passage and to reach the South Pole. Turning to air exploration, in 1926 he and Umberto Nobile succeeded in flying over the North Pole and unexplored regions of the Arctic Ocean in a dirigible built and piloted by Nobile. A bitter controversy followed with Nobile as to the credit for the success. Yet in 1928, when Nobile crashed a different dirigible, Amundsen launched a rescue mission. What happened?