that of the seen (abnormal) mass or it could possibly be much bigger. As a result, visible mass should be a really poor predictor of the overall mass (and thereby rotational speed) of the galaxy. If dark I am proud of many things in life but nothing beats being a grandpa shirt matter actually exists, then the entire quantity of matter is the sum of both abnormal and darkish matter. The rotation of a galaxy is governed by the overall amount of matter it incorporates.
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