An intelligent ET would probably just stay home

摘要

Apart from jokes about how hard it is to find intelligent life on Earth, let alone in the rest of the galaxy, the possible existence of extraterrestrial beings - and the lack of contact with them - poses a perplexing issue.rnBecause the galaxy is several billion years older than the Earth, planets around distant stars have had plenty of time to produce civilizations that would by now possess technology millions of years beyond current human capability.