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A galaxy is a collection of stars and other astronomical bodies, including planets, comets and asteroids, held together by gravity.

Galaxies come in different shapes and sizes. These include the spiral, barrel-spiral and elliptical. Our galaxy called the Milky Way, is approximately 100.000 light years in the width and contains over 100 billion stars.

The center of galaxies can contain many young, very hot stars as well as older stars. Swirling clouds that have been energized by magnetic forces also exist in the center.

At this point in time, no one knows the exact number of galaxies in the universe. Astronomers are, however, learning more and more about them every day.

Source: sites.google.com

Who learns more about galaxies every day?