Considerations on the Seventh Parameter

As can be seen from Fig. 20.11 b, we have found an average duration of galactic civilizations of about 50,000 years with a deviation of 7000 years. Now assuming a reasonable duration of a planet’s life in the habitable zone of about 7 billion years (Gy) (remember that the third Drake parameter assures us this), the value of the temporal fraction of a civilization’s life is 7.3 × 10−6 with a deviation of 10−6. This means that our galactic civilization has a total time of about 50,000 years, starting from our current technological level, during which it can recognize and be recognized by other civilizations.