"Star Trek offers an almost infinite number of exciting Science Fiction stories, thoroughly practical for television? How? Astronomers put it this way: Ff^2 (MgE) - C^1R1^1 x M = L/So Or to put it in simpler terms, by multiplying the 400,000,000,000 galaxies (star clusters) in the heavens by an estimation of average stars per galaxy (7,700,000,000,000,000,000,000,000,000,000,000), we have the approximate number of stars in the universe, as we understand it now. And so… …if only one in a billion of these stars is a "sun" with a planet...<br /[A]nd only one in a billion of these is of earth size and composition... [T]here would still be something near 2,800,000,000,000,000,000,000,000,000 worlds with a potential of oxygen-carbon life... [O]r...(by the most conservative estimates of chemical and organic probability), something like three million worlds with a chance of intelligent life and social evolution similar to our own."