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Topics: Galaxies
Galaxies
Galaxies are gigantic systems of stars and interstellar matter of dust and gas, dark matter, black holes, quasars and all kinds of celestial bodies. They are typically consisted of several million or trillion stars and stellar remnants, separated by millions of light years distance and gravitationally bounded. Traditionally classified according to their shape, the most common types of galaxies are the elliptical and the spiral galaxies.
