Dear Dr. Staff: Why is the sky blue? My pappy told me that it's because it reflects the ocean, but then my science teacher told me that it's some sort of reflection in the atmosphere or something, like a rainbow that's only colored blue, and covers the whole sky. Why would anybody want a rainbow like that? Who was right, my pappy, or my teacher?
Dear Future Atmosphere: Neither one was right. You see, when galaxies and stuff move away from us, there's this thing called "red shift", which means that their colors become a little bit more red. Well, the opposite of red shift is called "blue shift", and it means that things moving towards us become blue. You've probably heard about all the little flecks of dust and junk that are always falling to the earth from outer space. Well, all these are moving towards us, and, because of the blue shift, they turn real blue because there are so many of them and they're so close.
