In the equation: Number of Civilizations =Np × flife × fcivilization × fnow
What do we mean by fnow?
A)the fraction of planets with civilizations on which the civilizations exist now
B)the fraction of time since the Big Bang represented by the present era
C)the fraction of all species ever to exist that we currently are aware of
D)the fraction of planets in the galaxy on which a civilization could theoretically develop now
E)the fraction of civilizations in the universe that currently are sending messages to us

Question

Quizplus · Accepted Answer

fnow refers to the fraction of planets with civilizations on which the civilizations exist now, indicating the proportion of civilizations that are currently alive and active at the same point in time as us.

In the Equation: Number of Civilizations =Np × Flife ×