Galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas dust, and an important but poorly understood component tentatively dubbed dark matter.
Can you belive that there are at least 100 billion galaxies in the universe? Yes, there are! Small galaxies have 10 billion stars, and big galaxies have one trillion stars! Galaxies have beenaccording to their apparent shapes. They include elliptical, spiral, and peculiar galaxies (with irregular or unusual shapes). Interactions between nearby galaxies, which may cause them to merge, may enhance star , producing a star burst galaxy.
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