🌄 Mountain Valley Sunrise: Sun Elevation, Shadow and Mist Visibility (2D)

Cross-section of a valley with an eastern ridge, an observer and a distant summit as the sun rises. Set the latitude, date, summit height and distance, ridge elevation, mist visibility and mist depth, and see when the sun reaches the summit and the valley floor, how long the shadows are, and how much of the summit light survives the mist. Sunrise, shadow, Beer-Lambert extinction and the Koschmieder rule are checked with four in-page numerical checks.