Lunacy!?

(Picture courtesy of the NASA, Astronomy Picture of the Day Archive)

"When the moon hits the sky like a big pizza pie, that's.......an illusion?" Actually the moon is really there on the horizon but the "big" part is the illusion. It is a common trick played on us by our brains. The crazy thing is there is no change in the moon's size when it is on the horizon and when its above us in the sky. I know what you are thinking......Todd you're crazy, I saw the full moon rising and it was huge! Yes, it appeared huge, but really it wasn't. Our brains tend to think of it this way, if a distant object like the moon is perceived to be on the horizon it must be closer and if it is closer than it must be bigger. Our brains have never known the opposite. Simply put, the closer you get to something the bigger it appears. And strangely enough the moon always stays roughly 239,000 miles from us in its orbit, always. There is another theory that the atmosphere magnifies the image of the moon making it appear larger when it is lower to the horizon. Scientist agree that the atmosphere doesn't have the properties to create that kind of effect. Well, there is a simple test you can do to find out if this "growing" moon is in fact a product some strange scientific blend of physics or simply a crazy illusion created by your brain. Next time there is a full moon on the low horizon that looks bigger than normal, take something small like an eraser on your pencil or even your pinky finger and hold it at arms length with one eye closed. Measure the size of the moon in comparison to that object then do it again later when the moon appears smaller. You should notice that the moon did not change in size, but your brain in fact is a "Luna"tic. :-)