Explain why the sky is blue during the day but yellow at sunset! Amaze your students with this glass egg that acts like a little piece of the sky. The egg looks blue when light passes through a small part of it. But when light passes through a large amount, it appears yellow. Just like the sky! At sunset, the sun's light is passing horizontally through a thick layer of atmosphere and appears yellow. But during the day, the sun's light passes nearly vertically through much less atmosphere, and so it appears blue. The reason is that short wave blue light is more frequently scattered by air molecules than longer wave red and yellow light. So during sunset the blue light is already scattered away before the light finally reaches your eye. The Sunset Egg demonstrates these same phenomena using microscopic glass dye particles (cobalt oxide) to substitute for air molecules. This product is not a toy. Adult supervision required.
