Alien Encounters: Earth's Most Alien Places
Bizarre creatures called "extremophiles" are found in some of Earth's most toxic and intense environments. How can studying these life forms help us understand alien life?
Most Watched in Aliens & UFOs
Alien Encounters: A Space-Powered Alien Ship
An alien spacecraft might not rely solely on sunlight to power its trajectory. Find out what other energy technology aliens could use to travel through the universe.
Alien Encounters: Frank Drake and Nick Sagan Meet Again
Author Nick Sagan hasn't seen his godfather, Frank Drake, in over 30 years. We capture their reunion - and find out how Drake became friends with Nick's famous father, Carl Sagan, in this exclusive clip.
Alien Encounters: Earth's Most Alien Places
Bizarre creatures called "extremophiles" are found in some of Earth's most toxic and intense environments. How can studying these life forms help us understand alien life?
Alien Encounters: Will Aliens Have Bodies?
Will ETs look like us? Will they resemble giant insects? Scientists debate how various environments could have created life forms beyond our wildest imagination.
Recent Videos in Aliens & UFOs
Alien Encounters: Frank Drake and Nick Sagan Meet Again
Author Nick Sagan hasn't seen his godfather, Frank Drake, in over 30 years. We capture their reunion - and find out how Drake became friends with Nick's famous father, Carl Sagan, in this exclusive clip.
Alien Encounters: A Space-Powered Alien Ship
An alien spacecraft might not rely solely on sunlight to power its trajectory. Find out what other energy technology aliens could use to travel through the universe.
Alien Encounters: Earth's Most Alien Places
Bizarre creatures called "extremophiles" are found in some of Earth's most toxic and intense environments. How can studying these life forms help us understand alien life?
Alien Encounters: Will Aliens Have Bodies?
Will ETs look like us? Will they resemble giant insects? Scientists debate how various environments could have created life forms beyond our wildest imagination.