sundrun
Sundrun refers to a phenomenon observed in certain regions where the sun appears to set and then rise again shortly thereafter, creating the illusion of a double sunset. This effect is typically caused by atmospheric refraction, where light bends as it passes through layers of air with different densities. In areas with significant temperature inversions, such as coastal regions or valleys, the warm air above cooler air can create a prism-like effect. As the sun approaches the horizon, its light rays are bent upwards, making it appear higher in the sky than it actually is. This can lead to the sun seeming to set, dip below the horizon, and then reappear due to the continued refraction. The duration and intensity of the sundrun effect vary depending on the atmospheric conditions and geographical location. While it is a natural optical phenomenon, it has sometimes been mistaken for supernatural events in folklore and mythology. Scientific explanations, primarily involving atmospheric optics, are widely accepted for its occurrence.