Photograph by Carmem L. Vilanova UNIVERSAL LIFELINE: Even
Stephen Hawking has warned against connecting with
extraterrestrial life forms. E.T. Stay Home? We haven't heard
from space aliens, and that might be good news By Ronald Bailey
If extraterrestrial civilizations exist in our galaxy—and there
are good reasons to think they do—it's probably a good idea to
mind our own business and hope they do the same. There seems to
be plenty of available real estate for extraterrestrials to live
on. In the past few years, astronomers have identified over 500
planets circling nearby stars. Extrapolating these findings, it
is likely that tens of trillions of planets revolve around the
hundreds of billions of stars that make up our home galaxy.
Trillions of these planets could have Earth-like
characteristics; i.e., rocky with liquid water. In a 2008
article in the journal Astrobiology, University of East Anglia
researcher Andrew Watson calculated the probability that
intelligent life will emerge on Earth-like planets is q