On 15 October 1991, scientists at the University of Utah detected a single subatomic particle travelling at a speed so close to light that it defied the known laws of physics. The Oh-My-God particle, as it became known, carried energy forty million times greater than anything human accelerators can produce, and its origin remains unexplained three decades later. That same date marks the first tethered human balloon flight in 1783, when Jean-François Pilâtre de Rozier rose 26 metres above Paris and launched the age of aviation. In 1066, Edgar the Ætheling was briefly proclaimed King of England, only to submit to William the Conqueror within weeks. And in 1582, Pope Gregory XIII introduced the Gregorian calendar, erasing ten days from October to correct centuries of astronomical drift. Clara Vale explores a day that saw particles break cosmic speed limits, humans leave the ground, kings vanish into footnotes, and time itself get edited.