Lecture 13 Flashcards
The complete version of the Drake equation allows us to estimate the number of
intelligent civilizations capable of communicating in our galaxy now
If SETI is successful, and we discover another communicative (technological) civilization, what is the important implication for our own civilization?
that L is not necessarily short, and we too can survive technological adolescence
Which of the following factors in the Drake equation is best known?
Ne the number of habitable planets in our galaxy
Which of the following factors in the Drake equation is least well known?
L fraction of civilization-bearing planets that have intelligent civilizations on them now
Suppose there are a million habitable planets in our galaxy, that one in ten are habitable, that one in a thousand planets with life had at some point had an intelligent civilization, and that one in a hundred civilizations that has ever existed is in existence now. Given this, how many civilizations are in existence now?
1
Given that life on Earth appears to have arisen quite easily and rapidly suggests that the factor fl, in the Drake equation could be close to
1
Which of the following cases in the Drake equation would be the minimum necessary condition for us to be the only intelligent civilization currently in our galaxy?
any one of the factors to be close to zero
The factor L, in the Drake equation depends on
how long civilizations survive once they have arisen
The ratio of an animal’s brain weight to body weight is thought to be roughly
proportional to its
Intelligence
In the Drake equation, a value of flife that is close to one and a value of f civ that is close to zero would imply:
Primitive life is common, but intelligent life is rare
Suppose that we discover life on Mars with an origin independent of life on Earth.
Which term in the Drake equation would be most affected?
flife
