[ Pobierz całość w formacie PDF ]
serious scientific investigation. The issue seemed a subject fit only for speculative writers. Today, after
American and U.S.S.R. space probes have visited planets in our solar system and radio astronomy has
radically reshaped our traditional concepts of the cosmos, there has been a revolutionary change of
attitude among many scientists on the possibility of some form of higher extraterrestrial life existing in
other solar systems.
The new attitude is reflected in a statement from a report issued in 1972 by the Astronomy Survey
Committee of the U.S. National Academy of Sciences:
Each passing year has seen our estimates of the probability of life in space increase, along with our
capabilities for detecting it More and more scientists feel that contact with other civilizations is no
longer something beyond our dreams but a natural event in the history of mankind that will perhaps
occur within the lifetime of many of us. The promise is now too great, either to rum away from it or to
wait much longer before devoting major resources to a search for other intelligent beings. ... In the
long run this may be one of science's most important and most profound contributions to mankind and
to our civilization.
A landmark study of the subject, Intelligent Life in the Universe, by the Soviet astrophysicist I. S.
Shklovskii of the Sternberg Astronomical Institute in Moscow and the American exobiologist and
astronomer Carl Sagan of Cornell University, authoritatively outlined the current state of scientific
knowledge of the biological origins of living organisms on a planet such as the earth and convincingly
demonstrated the possibility that the conditions necessary for the evolution of higher life forms may be
present on countless planets scattered throughout the cosmos. While stressing the speculative nature of
some of their ideas, the authors estimate that in the future not only interstellar communication but
flight eventually will be achieved. "Especially allowing for a modicum of scientific and technological
progress within the next few centuries," Sagan stated, "I believe that efficient interstellar space-flight
to the farthest reaches of our Galaxy is a feasible objective for humanity. If this is the case, other
civilizations, aeons more advanced than ours, must today be plying the spaces between the stars."
That such conclusions about interstellar life and flight are regarded not only as possible but highly
probable by an increasingly large portion of the world scientific community was demonstrated by the
first international conference, held in 1971 at the Byurakan Astrophysical Observatory in Soviet
Armenia, devoted to the question of contact with extraterrestrial life. At this week-long gathering co-
sponsored by the U. S. National Academy of Sciences and the U.S.S.R. Academy of Sciences,
numerous prestigious astronomers, physicists, biologists, anthropologists, linguists, egyptologists,
sociologists, and archaeologists from different nations agreed that "the chance of there being
extraterrestrial intelligence is much greater than scientists thought possible a few decades ago" and
that recent discoveries have transferred some of the problems of detecting other civilizations in the
cosmos "from the realm of speculation to a new realm of experiment and observation."
In a 1975 article in Scientific American, Carl Sagan and Frank Drake, who headed an earlier detection
experiment called Project Ozma in West Virginia, summarized the new awareness of the probability of
life existing elsewhere in the universe:
From the movements of a number of nearby stars we have now detected unseen companion bodies in
orbit around them that are about as massive as large planets. From our knowledge of the processes by
which life arose here on the earth we know that similar processes must be fairly common throughout
the universe. Since intelligence and technology have a high survival value it seems likely that
primitive life forms on the planets of other stars, evolving over many billions of years, would
occasionally develop intelligence, civilization and a high technology. Moreover, we on the earth now
possess all the technology necessary for communicating with other civilizations in the depths of space.
Indeed, we may now be standing on a threshold about to take the momentous step a planetary society
takes but once: first contact with another civilization.
Yet Sagan, Drake, Shklovskii, and most other reputable scientists involved in this experimental search
emphasize that what is meant by "extraterrestrial life" is most certainly not the incredibly humanoid
"ancient astronauts" conjectured largely from Latin-American artifacts and legends by Erich von
Daniken and other writers following his fallacious but popular reasoning in Chariots of the Gods?
(1970); nor are real extraterrestrials likely to resemble the benevolent blond Venusians or little green
Martians claimed to have been sighted by some UFO contactees. These fantasies about alien life
reflect an unimaginative, egotistically anthropocentric cosmology in which all living creatures in the
universe are merely duplications of us, mirrors of our features and fears.
A more rational, less self-centered cosmological viewpoint, rooted in scientific logic, will admit that
extraterrestrials, if they exist, are not likely in any way biologically to resemble what we know on our
small planet. "Life, even cellular life, may exist out yonder in the dark," comments naturalist Loren
Eisley in his book The Immense Journey. "But high or low in nature, it will not wear the shape of man.
That shape is the evolutionary product of a strange, long wandering through the attics of the forest
roof, and so great are the chances of failure, that nothing precisely and identically human is likely ever
to come that way again."
Though life beyond the earth will not assume our shape, we will be related - by the fact that we inhabit
the same universe and evolved from the same elements forged in the violent depths of the stars. We
are all made, to quote Sagan, "from the dregs of star-stuff." The new cosmological picture emerging
today, from ground-based and space astronomy, encourages us to see ourselves and our planet as an
infinitesimal but closely related part of an immense, active universe which was created, according to
[ Pobierz całość w formacie PDF ]