We are not alone in the universe. A few years ago, this notion seemed farfetched; today, the existence of extraterrestrial intelligence is taken for granted by most scientists. Even the staid National Academy of Sciences has gone on record 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 in the lifetime of many of us." Sir Bernard Lovell, one of the world's leading radio astronomers, has calculated that, even allowing for a margin of error of 5000%, there must be in our galaxy about l 00 million stars which have planets of the right chemistry, dimensions, and temperature to support organic evolution. If we consider that our own galaxy, the Milky Way, is but one of at least a billion other galaxies similar to ours in the observable universe, the number of stars that could support some form of life is, to reach for a word, astronomical. As to advanced forms of life-advanced by our own miserable earth standards-Dr. Frank D. Drake of the National Radio Astronomy Observatory at Green Bank, West Virginia, has stated that, putting all our knowledge together, the number of civilizations which could have arisen by now is about one billion. The next question is, "Where is everybody?"
Even the staid National Academy of Sciences has gone on record 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 in the lifetime of many of us." Sir Bernard Lovell, one of the world's leading radio astronomers, has calculated that, even allowing for a margin of error of 5000%, there must be in our galaxy about l 00 million stars which have planets of the right chemistry, dimensions, and 
temperature to support organic evolution. If we consider that our own galaxy, the Milky Way, is but one of at least a billion other galaxies similar to ours in the observable universe, the number of stars that could support some form of life is, to reach for a word, astronomical. As to advanced forms of life-advanced by our own miserable earth standards-Dr. Frank D. Drake of the National Radio Astronomy Observatory at Green Bank, West Virginia, has stated that, putting all our knowledge together, the number of civilizations which could have arisen by now is about one billion. The next question is, "Where is everybody?"
