Project Cyclops, A Design... - Department of Earth and Planetary ...

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2. LIFE IN THE UNIVERSE
"Absence of evidence is not evidence of absence."
Martin
Rees
It is only recently that speculation about the existence
of intelligent extraterrestrial life has turned into
serious scientific study. As recently as 40 years ago,
almost all scientists, speaking ex cathedra, would have
argued that life, if not unique to earth, was at least
exceedingly rare. The last 15 years have brought about
an almost complete change of opinion. Today a large
segment of the scientific community is willing to accept
the belief that life is common in the universe and indeed
that many civilizations have existed and still exist in our
Galaxy, and that many may be more advanced than our
own. Indeed, the debate is now concerned primarily
with how best to discover these civilizations rather than
with the plausibility of their existence.
We still do not have "hard" scientific evidence for the
existence of intelligent extraterrestrial life, evidence
amounting to proof-evidence in the sense Rees uses the
word in the quotation above. In fact, it is unlikely that
we will ever have this kind of evidence unless and until
we actually search for and succeed in contacting other
life. To justify such an effort, which may require billions
of dollars and decades of time, we must truly believe
that other intelligent life exists and that contact with it
would be enormously stimulating and beneficial to
mankind. What is it that gives us such faith, and the
audacity to suggest such an undertaking? What has
caused such a reversal of conventional scientific thought
over the last few years?
CONVERGING
DISCIPLINES
Historically, science has been concerned with the
gathering of data, careful measurement and analysis, and
the construction of models in a number of seemingly
unrelated disciplines. Little connection was seen, for
example, between astrophysics and biology or between
these and communication theory. The last two decades
have witnessed a synthesis of ideas and discoveries from
previously distinct disciplines. Out of this synthesis have
grown new fields of research. Thus we now have
exobiology, which represents a synthesis of discoveries
in astronomy, atmospheric physics, geophysics, geochemistry,
chemical evolution, and biochemistry.
This burst of interdisciplinary thought has produced
an understanding of life in the universe based, for the
first time, on scientific information. To be sure, the
picture is incomplete; many details are missing but the
broad picture is emerging. It is as if science, having spent
three centuries doing its humble and arduous homework,
had finally become competent to address itself to the
most fundamental questions of all, the questions asked
by children and philosophers: How did it all begin? What
am I? Quo vadimus?
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The picture we behold is one of cosmic evolution: a
universe that was born, has evolved into galaxies of stars
with planets, and into living things, and that will
continue to evolve for aeons before vanishing into
oblivion or collapsing toward rebirth. We owe our very
existence to strange and wonderful processes that are an
inherent part of this cosmic evolution. For example, we
know that heavy elements were not present in the
beginning but are formed in the fiery interiors of stars,
many of which die in a titanic explosion. The dust of the
heavy elements hurled into space becomes the raw
material from which new stars with earthlike planets can
form. The calcium in our very bones was manufactured
in the cores of countless long dead stars not unlike those
that sparkle in our night sky.
The ability of intelligent life to contemplate its own
existence has always fascinated the philosopher. Now we
see the even more fascinating picture of the entire
universe contemplating itself through the minds and eyes