What defines a galaxy as a structure within the universe?
Answer
A massive gravitationally bound collection of stars, gas, dust, and dark matter
Galaxies are complex, large-scale systems held together by mutual gravitational attraction. They are primarily composed of vast quantities of stars and stellar remnants, along with significant amounts of interstellar gas and dust. Crucially, they are dominated by dark matter, which serves as the gravitational scaffold that supports and organizes the visible components of the system.
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