The Search for Extraterrestrial Intelligence (SETI) has been scanning the cosmos for signs of intelligent life for over 50 years. However, the portion of the universe we've surveyed is incredibly small compared to its vastness. To put it in perspective, our exploration is equivalent to a mere ...

Stream Full Episodes of NASA's Unexplained Files: https://www.discoveryplus.com/show/nasas-unexplained-files From Season 4, Episode 8: Mars's Deepest Secret Martian dunes are massive and unlike ours. Subscribe to Science Channel: http://bit.ly/SubscribeScience Like us on Facebook: ...