The next time you look up at the sky and see it's blue, you can remember that it's because the sunlight is being scattered by the tiny molecules in the air around us. Also, when the sun's light ...

If Earth had no atmosphere like the Moon there would be no scattering, and the sky would remain black, even in daylight ...

and the outer edge is blue with light refracting at an angle of 22.37 degrees. You will usually see a Sun dog when the Sun is lower in the sky, so typically in the morning or evening. Just like ...