Are there any subjects in astronomy that are considered closed books?

I cannot think of any, but this depends on your standards of evaluation. Everything depends on the size of your domain, within which your theories apply with good precision and account for more than 90 percent of the objects and situations you see. Then there is that last 10 percent where our knowledge is less secure and where there are technical details that remain to be worked out. There are a couple of areas that, in astronomy, are the most well developed. The evolution of isolated stars is pretty much a closed book if you are satisfied with not knowing exactly how a star was first formed, or how it will evolve in its very old age. We can account for the appearances of millions of stars, provided we do not ask detailed questions such as whether they have 'sunspots' or 'coronae', and ask the theory to predict with better than 1 percent accuracy the temperature or luminosity of the star at any time in its evolution.

For celestial mechanics, we pretty well know the details of the solar system to very high precision, however, we know that our theories are limited in what they predict by the accuracy of our measurements. We cannot measure the location of a planet to an accuracy of one centimeter, nor its mass to a few grams, and it is these inaccuracies that contribute to 'chaotic' motion as we predict where things will be in the far future.


Copyright 1997 Dr. Sten Odenwald
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