Is There Life on Other Planets?
It seems certain that at least a tiny percentage of the stars in our vast Universe have planets orbiting them. If so, then surely a minute percentage of those planets—billions of them—must be capable of sustaining life. And of those billions, how many contain life at least as advanced as ours? Isaac Asimov examines the dramatic prospects of life “out there,” within our Solar system and beyond.
There is actually a fairly nice and breezy examination of the realities of extraterrestrial life for a young audience. Although it is itself top-notch, older readers might prefer something a bit more sedate and thorough such as Extraterrestrial Civilizations.