Things to Come

The new information on planetary formation, extraterrestrial chemistry, and the effect of the Earth's environment on the origin and development of life now provides a strong basis for looking for life (in fact, intelligent life) beyond the solar system. Such a search requires a much different approach than sending astronauts and spacecraft to nearby worlds. Because of the incredible distances to even the nearest stars, we need to search for some long-range manifestation of life that can be detected from Earth. We need to detect radio signals rather than metabolic chemical reactions. We need to explore different stars rather than just the planets around our Sun. And finally, we need to use a different technology, radio astronomy, rather than spacecraft. We can now define a program to search for intelligent signals of extraterrestrial origin by using our existing radio telescope antennas with only a small amount of sophisticated auxiliary equipment. The technology needed for such a search is clearly at hand at this very moment.

After only two decades of active research, scientists have compiled an impressive list of accomplishments and discoveries in the search for the origin of life. Studies pursued under the auspices of the space program have contributed to a more universal understanding of the phenomenon of life as a whole. We now have considerably more details than we did thirty years ago. We have direct knowledge of the properties of the Moon, Mars, Venus, Mercury, and Jupiter. We have a wealth of information on proteins and cells, on the low likelihood of life on other planets in the solar system, and on the forces that led to the formation of the solar system and biomolecules. We have found simple organic substances, believed to be the precursors of life, in planetary atmospheres, in meteorites, in comets, and in interstellar space. We can also synthesize them quite readily in laboratory experiments.

To discover an independent life form on another planet, or even beyond the solar system, still presents a challenge unequalled in the history of scientific inquiry. Although our knowledge has increased dramatically over the past few decades, our ability to obtain new knowledge has increased even more. The Earth's oldest rocks, newly found meteorites, our laboratories, and our huge, sensitive radio telescopes all have important roles to play as we continue our efforts to learn the chemical and biological secrets of ancient Earth and our studies on the existence, nature, and distribution of life in the universe.

SeleetedReadings

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DeVincenzi, D. 1976,
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Feinberg, G. and R. Shapiro 1980,
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French, B.M. 1977, Mars:
The Viking Discoveries
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Goldsmith, D. and T. Owen 1980,
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Miller, S. and L. Orgel 1974,
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Shklovskii, I.S. and C. Sagan 1968,
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