extraterrestrial life

   The question of whether or not mankind is alone in the universe is one of the oldest problems of philosophy, and has deep implications for our world view. In recent years, the subject has become increasingly important to science too. Advances in biochemistry and molecular biology have begun solving the mystery of the origin of life. Discoveries in astronomy are casting light on the existence of other planets and their chemical and physical structures, while the space programme has provided the opportunity to search for life directly on our neighbouring planets. In addition, a major new project has begun which sets as its goal the detection of radio signals from advanced technological communities elsewhere in the galaxy. It is therefore very timely to consider in detail what the discovery of extraterrestrial life would mean for our view of ourselves and our place in the cosmos.
   There is little doubt that even the discovery of a single extraterrestrial microbe, if it could be shown to have evolved independently of life on Earth, would drastically alter our world view and change our society as profoundly as the Copernican and Darwinian revolutions. It could truly be described as the greatest scientific discovery of all time. In the more extreme case of the detection of an alien message, the likely effects on mankind would be highly significant.[2003年、東京農工大]

biochemist生化学　　　
molecular biology分子生物学
detection発見　
extraterrestrial地球外の　
microbe　微生物

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