Friday, September 24, 2010
I've been trying to figure out why I can't focus on close objects. I know that the atmosphere can bend light, and I think this is related to my problems.
At the horizon, light from the sun or moon has to travel through more air than it does slightly above the horizon. This is why the sun and moon look like ovals instead of circles when they're on the horizon. In fact when the bottom of the sun's disk appears to be just touching the horizon, it is actually below the horizon, but the atmosphere bends the sun's image up into view.
So it stands to reason that the atmosphere has changed recently, causing my focusing difficulties. I don't know whether the air is more dense than it was, or less dense. If it's more dense, than it's probably caused by the same thing as my weight gain, Eath's gravity has increased!
I'll have to keep looking into it...