There is something you see almost every day that is round and that would be our Sun. Our closest star only deviates from being a perfect sphere by 17 : 1,000,000. Now I bet you can't see that small amount of out of roundness. So you may ask, why doesn't it bulge at its equator, also? Because of the huge thermo-nuclear reaction going on in its center which creates huge pressures pushing outward against its huge gravity pulling inwards. Things will change, though, when the sun starts running out of fuel. Now, that could be a subject for a future blog, or maybe not. Now you all have a bright and sunny day today, you hear?
Wednesday, November 14, 2012
Wondering about round things.
Have you ever seen a perfect circle? Or how about a perfect sphere? I don't believe you have; I haven't. Let see, ball bearings are pretty close to being a perfect sphere as are a lot of things. Probably the smaller something is the more it will appear to be a perfect sphere because a very small fraction of a percent out of round would be so small it wouldn't be noticed. OK, lets think huge. You may tell me that the moon is round, or the Earth is a perfect sphere, or the planets are. You would be wrong. The earth (and other planets) bulge at their equator and the faster spinning ones bulge the most from centrifugal force.