We've come a long way since 1600, when Giordano Bruno, a defrocked priest from Naples, was burned at the stake for espousing, among other things, his belief that there might be other worlds and other life-forms beyond Earth. In our Star Trekking age, it's now almost heretical not to believe in extraterrestrial life--a belief that will surely be fortified by last week's announcement of the discovery of two Saturn-size planets around two distant stars.
Polls show that 54% of Americans are convinced that there are aliens out there, to say nothing of the significant fraction (30%) who suspect we've already been...