Why Haven’t We Met Any Aliens Yet?

Space





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Seriously, where is everyone? Albert Ziganshin/Shutterstock.

It is estimated there are 100 billion planets in the Milky Way, itself one of hundreds of billions of galaxies. On one planet, Earth, we know life arose, but there should be millions of Earth-like habitable planets in our galaxy alone with the capability to support life. This begs the question: Where is everyone else?