Concept explainers
Explain all answers clearly, with complete sentences and proper essay structure if needed. An asterisk (*) designates a quantitative problem, for which you should show all your work.
*22 Time Between civilizations. Suppose that there are loo billion stars in the Milky Way Galaxy, that 1 in 1 million stars gets a civilization at some point, and that these civilizations have arisen at random times over the past 5 billion years. On average, how much time separates the rise of one civilization in the galaxy from the rise of the next? Eased on your answer, should we expect to make radio contact with another civilization that is either at or below our own current level of technological development?
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