Cycles

I continue my examination of relationships with a pattern as obvious as night and day: cycles. Each day the sun rises in the east, traverses the sky, and sets in the west; each month the moon waxes and then wanes; and each year cycles through its four seasons. Water evaporates; condenses in the sky; falls back to Earth; collects in streams, lakes, and rivers; and finally flows to the seas and oceans to begin the cycle anew. And plants and animals pass through various stages in their life-cycles.
    Scientists have also identified a seven-stage life-cycle for stars. The life of a star, they calculate, ranges from forty thousand years to tens of billions of years depending on the star’s size. Obviously, no one ever has, or ever will, observe the entire life of a star. How could scientists have even thought of stars having life cycles? That takes us back to the sets and subsets I mentioned two weeks ago.
    To us, stars began as the spots of light shining in the night sky. As people studied them and developed tools to see them more clearly, they realized there were different types, or subsets, of stars. They then recognized similarities to things that are not stars, things that live and grow. Scientist began to theorize that, just as plants and animals pass through various stages, so, too, do stars. Stars are not living beings, but because of their similarity in passing through stages , scientists identified a life-cycle of stars. They are born when a vast field of space particles collect together until they are dense enough to trigger fusion of hydrogen atoms into helium atoms. They live like this until the Hydrogen is expended and then they die. What can we learn from this?
    Firstly, we won’t begin to examine anything until we first notice it and then observe it closely enough to notice differences. Secondly, we understand things better by comparing them to things with which we are more familiar, noting similarities and differences. We don’t understand anything in isolation, without relating it to other things. Thirdly, being similar to something is not being that thing. Having a life-cycle is a useful analogy for studying stars, but we do not believe that stars truly live.

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