Halley's equation

Halley’s equation describes the timing of Halley’s Comet’s returns based on its orbital period. It predicts that the comet reappears approximately every 75 to 76 years, following a predictable orbital pattern around the Sun. In essence, the equation helps astronomers estimate when the comet will be visible from Earth again, factoring in its orbital velocity and distance from the Sun. This allows for accurate tracking and forecasting of its appearances, which historically have been observed, recorded, and celebrated as significant celestial events.