Skylight.Residents of northern Idaho and eastern Washington
v. Past tense and past participle of spy. an unusual light show last summer. Wispy wisp n. 1. A small bunch or bundle, as of straw, hair, or grass. 2. a. One that is thin, frail, or slight. b. A thin or faint streak or fragment, as of smoke or clouds. 3. clouds went from white to bright--displaying all colors of the rainbow. The multicolored marvel wasn't a typical rainbow. Rather, it was a rare phenomenon called a circumhorizon arc. Several ingredients are needed to set the sky alight this way. First, clusters of ice crystals must form. These often form in cirrus clouds, feathery feath·er·y adj. 1. Covered with or consisting of feathers. 2. Resembling or suggestive of a feather, as in form or lightness. feath clouds that grow more than 6 kilometers (3.7 miles) above Earth's surface Noun 1. Earth's surface - the outermost level of the land or sea; "earthquakes originate far below the surface"; "three quarters of the Earth's surface is covered by water" surface . Because the air temperature there is below freezing, cirrus clouds are made up of ice crystals instead of liquid water droplets. Next, the sun's rays must be perfectly aimed at the ice crystals. The light waves have to enter the crystals along vertical surfaces and exit the ice crystals along horizontal surfaces. As each light wave crosses these surfaces, it refracts. This bending separates each light wave into several new waves, each with a different wavelength. Each wavelength paints the sky in a different color. For instance, a wave with a long distance between its peaks creates a band of red light. Sky-watchers on that summer day had to snap their photos quickly, because the arc-malting conditions lasted only about an hour. |
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