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Islam Hassan
Feb15-13, 10:57 AM
P: 149
Imagine a very big, opaque planar disk blocking the sun's direct rays which is placed horizontally at a high elevation.

Is it possible that such disk, by blocking the sun's direct rays but allowing the peripheral blue light of the rest of the sky to shine through, would enable us to actually see and bathe in the blue light of day *only*? The disk would have to be very large to exclude direct sunlight impinging too close around the point of observation and drowning out the weaker blue light of the sky (Raleigh scattering light).

Would we be able to see such blue light exclusively, or would direct sunlight (impinging on the ground at a distance) always be too strong and 'drown out' the weaker blue light? At what elevation would such disk have to be placed and how big would it have to be for the blue light to actually be seen?

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