Wandering through the realms of the cosmos, pondering its huge vastness

Posts tagged “blue-violet sky

Pink Contrail and the Crescent Moon

On the walk from our house to the street one afternoon,  a nice sight in the western sky caught my eyes — the  27% illuminated waxing crescent Moon and a pink-colored sunlit contrail against a blue-violet sky. This contrast of colors looked just fascinating. 🙂

Fortunately, I brought my Kodak digital camera with me so I was able to take a picture of it. The image turned out to be a bit blurry though without using a sturdy tripod.

Notice that while both the Moon and the cloud were illuminated by the same Sun, the cloud was pink and the Moon was so white. The answer lies in the fact that the atmosphere absorbs and scatters the shorter (blue) wavelengths of light, while allowing the longer (red) wavelengths through. The low angle afternoon sunlight arriving at the cloud (contrail) had traveled through significantly more atmosphere than the more “pure” sunlight reflected by the Moon.

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