Lunar Corona and ISS - Imaged by Tamás Ladányi (site, TWAN) close to the church of Agios Nectarios near the village of Messanangros on the Greek island of Rhodes May 17th 2010.

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The misty pastel hued corona circling the moon is produced by water droplets in the thin cloud.

Waves striking each droplet are scattered, primarily at its surface. The outgoing scattered waves combine constructively or destructively to form a fringed diffraction pattern, a corona.

The pattern we see in the sky is from millions of individual droplet contributions. In any one direction some droplets are diffracting light (or not) towards the eye.

In general, atmospheric optics effects (halos, rainbows, coronae and glories) are produced by immense numbers of individual scattering particles. The pattern that a single particle would produce if projected on a screen is the same as that seen in the opposite direction in the sky from millions and millions of particles.

Why does the ISS track fade to red?

Diffraction by a single cloud particle to produce a corona pattern on a screen.