The universe is made up of Thousands of Galaxies. Our universe is infinite. For a long time, scientists thought the only galaxy was- our own. But around 1955, when NASA’s "Hubble Space" Telescope stared at a dark patch of sky for hours, and returned a picture of thousands of glittering galaxies no one had ever seen before, it launched a whole new question. And thus created the search for other galaxies. They eventually found that the number of galaxies in the observable Universe is 2 trillion. More than TEN TIMES what we originally thought!
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