Astronomers have been finding exoplanets out in the cosmos for 25 years, and if we've learned anything about all those planets, it's that a lot of different, weird kinds exist. They are big and hot and close to their stars. They are smaller than Earth. They are gassy and Jupiter-y. They are rocky and terrestrial. They are so cold even the most extreme earthly organisms would freeze to death. They are so hot they could melt glass. They rain glass. They are by themselves. They have neighbors. They are far away. They are right next door.
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