The search for extra-terrestrial life has been going for 50 years - but there's been a recent breakthrough. Astronomers have discovered a new planet called Gliese 581 c. It is the most Earth-like planet ever found. It orbits a star and may have habitats capable of supporting life. NASA hopes to find 50 more Earth-like planets by the end of the decade, all of which increases the chance that alien life has begun elsewhere.
Click here to to find out more about the Drake equation.
Click here to visit the SETI website.
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