I've heard that their is a formula involving seven variables of which top astronomers concur produces a factor

Question

I've heard that their is a formula of which top astronomers concur that produces a factor indicating an expected number of planets presently supporting intelligent biologically life in a giving area, for example 10000 for our galaxy and whatever for others and whatever raised to thrice whatever for our universe. What's it called? The 'm' factor or number or something like that. Now since most stars and therefor planets are towards the center of the galaxy and earths subgalactic proximity is roughly three quarters of the way out along the galactic radius then really 2500 of those planets would about the same galactic orbit as us and half of them are on the opposite side of the galaxy... Then 1250 planets would be avaible to us electromagnetically. In a larger galaxy like ours the journey would still take 12500 light years accounting for the 100000 light year diameter of the Milky Way. By this can we infer that only one planet is within 100 light years?

Answer 1

It's called the Drake equation. Unfortunately most of the variables that go into the equation are not known very well, but it's still a great way to begin a discussion on the possibility of intelligent life in the universe.

There are lots of sites on line that let you enter in your own values for the variables and it will do the calculation for you. Just do a search on "Drake Equation" in your favorite search engine.