A Fire Rainbow Over New Jersey
What is that inverted rainbow in the sky? Sometimes known as a fire rainbow for its flame-like appearance, a circumhorizon arc is created by ice, not fire. For a circumhorizon arc to be visible, the Sun must be at least 58 degrees high in a sky where cirrus clouds are present. Furthermore, the numerous, flat, hexagonal ice-crystals that compose the cirrus cloud must be aligned horizontally to properly refract sunlight like a single gigantic prism . Therefore, circumhorizon arcs are quite unusual to see. Pictured above , however, a rare fire rainbow was captured above trees in Whiting , New Jersey , USA in late May .