Crash courses and insights on the wonders of the universe, for all explorers, aliens, and other curious life forms out there seeking knowledge about the cosmos and beyond.

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Starry nights with clear skies are usually colder than a cloudy night. Ever noticed this? Why does it feel colder? Well, during the day, the sun heats up the Earth. But at night the heat is radiated back into the space. But when clouds are present, they act like an insulator and retain the radiated heat that would rather escape into the space without them in the way.