where does the name come from?
It is derived from the Greek word literally "milky".
Galaxy
The word galaxy is derived from the Greek "" (), literally "milky"
what is the galaxy? It is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.
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Galaxy [SEP] Introduction
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek "" (), literally "milky", a reference to the Milky Way. Galaxies range in size from dwarfs with just a few hundred million () stars to giants with one hundred trillion () stars, each orbiting its galaxy's center of mass. Galaxies are categorized according to their visual morphology as elliptical, spiral, or irregular. Many galaxies are thought to have supermassive black holes at their centers. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun.