A Fire Rainbow Over New Jersey

Astronomy Picture of the Day · 2008-06-10 · NASA (public domain)

A Fire Rainbow Over New Jersey — APOD for 2008-06-10

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 .

Astronomy Picture of the Day for 2008-06-10 — image & explanation courtesy of NASA (public domain), mirrored at Tukuk-OS for reading and search convenience.