Earths Beyond Earth: The Search for Other Worlds In early 1990, the first extrasolar planet was detected, surprising everyone by its strangeness. More planets have now been discovered outside our solar system than in it. These planets present many great mysteries to the astronomical world. Extrasolar planets are planets that exist outside our solar system; they are orbiting a star other than our Sun. So far, eighteen have been found, all of them defying well-established theories …showed first 75 words of 1254 total…

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