Large parts of Physics and Astronomy are a bit more like looking for your keys under the street lamp. You study what you can measure and model as simply as poss

Large parts of Physics and Astronomy are a bit more like looking for your keys under the street lamp. You study what you can measure and model as simply as possible the effects even if it's an approximation. The classic physicists response to a multi-body problem is 1,2, infinity...because those are the ones we have solutions/tools ffor. That's true for planets all the way to atoms. Now, at the edges there are those who look at more philosophical things like Bell's Theorem or study complicated things like chaos, but even there it's about simplifying to what you can model and measure... anything else is boiling the ocean and you never get done.