The Drake equation is used by astronomers to estimate the number of what in the Milky Way galaxy?
Correct answer: Alien civilizations
luckycatfay
How can you get to see more comments mine only allows the top few?
Katelyn The Gray Astrologer
FreakyGhost89057, 53 that are suitable in which 13 are more likely to be habitable.
FreakyGhost89057
Player #272443, and how many do we probably have?