Galaxies are typically classified into several types based on their shape and structure. Here are three main types of galaxies:
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Spiral Galaxies: These galaxies have a distinct spiral structure with arms that wind outward from the center. They typically contain a mix of young and old stars, along with gas and dust. The Milky Way, the galaxy that Earth is part of, is an example of a spiral galaxy.
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Elliptical Galaxies: These galaxies range from nearly spherical to elongated shapes and lack the distinct structure of spiral arms. They generally contain older stars and very little interstellar gas and dust, making them less active in star formation. Elliptical galaxies can vary in size from small dwarf ellipticals to giant ellipticals.
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Irregular Galaxies: These galaxies do not fit into the spiral or elliptical categories and often have an irregular shape. They are typically rich in gas and dust and are frequently sites of active star formation. Irregular galaxies can exhibit a variety of appearances due to gravitational interactions with other galaxies.
The galaxy that Earth is part of is called the Milky Way Galaxy, and it is classified as a spiral galaxy.