Math is the engine of the universe, driving and dictating all actions, interactions, transformations, and appearances, including yours. Equation-based laws underlie physical systems, and the physical systems astronomers care about are ones composed of stars, planets, galaxies, gases, plasma, strange subatomic particles, dark matter, dark energy, and anything else you might find if you ventured to space. Although all equations are beloved and have their own fan bases, some equations are more fundamental and wide-reaching than others.
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