Astronomy Picture of the Day -- A Circumhorizontal Arc Over Ohio

NASA ^ | May 24, 2014 | (see photo credit)

[SunkenCiv]

Explanation: Why would clouds appear to be different colors? The reason here is that ice crystals in distant cirrus clouds are acting like little floating prisms. Sometimes known as a fire rainbow for its flame-like appearance, a circumhorizon arc lies parallel to the horizon. For a circumhorizontal 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 in a collectively similar manner. Therefore, circumhorizontal arcs are quite unusual to see. This circumhorizon display was photographed through a polarized lens above Dublin, Ohio in 2009.

[SunkenCiv]

[Credit & Copyright: Todd Sladoje]

[SunkenCiv]

The Big One

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[IYellAtMyTV]

From my backyard, Spokane WA circa 2009. No polarized filters.

[Las Vegas Dave]

Great photos.

BTW: I was wondering if there was a pot-o gold at the end of that rainbow? < /humor >

[KoRn]

Wow! That’s awesome!

[GATOR NAVY]

Each one of your photos is better than the APOD photo. Thanks for posting them.

[SunkenCiv]

That only happens in Colorado. ;’)