Aliens in the Milky Way?

  • By Susan K. Lewis
  • Posted 07.01.08
  • NOVA scienceNOW

Microbes on Mars might be impressive, but the average Earthling would really be wowed by news of a full-blown, advanced civilization on a planet beyond our own. What's the likelihood that such a civilization exists in our galaxy? Explore the arguments, then take our poll: Do you believe ET is out there, capable of phoning home?

Launch Interactive

Do you think alien civilizations exist beyond Earth? Explore the arguments, then cast your vote.



(alien face)
© Yegor Tsyba/iStockphoto
(Earth, Milky Way, meteorite, sci-fi city, sci-fi spaceship, Hubble deep field, radio telescopes)
© NASA; (Antarctica) © Liesl Clark for WGBH/NOVA;
Courtesy of UNWF;
Courtesy of NOAA;
(equation, alien)

Related Links

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  • The Search for ET: Expert Q&A

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  • The Drake Equation

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  • Will We Ever Find ET?

    What are the odds that smart aliens exist in the universe?


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