Is Humanity Doomed? Insights from Astrobiology

Astrobiology, the study of life in the universe, offers profound insights into human sustainability. However, astrobiology is commonly neglected in sustainability research. This paper develops three topics connecting astrobiology to sustainability: constraints on what zones in the universe are habitable, the absence of observations of extraterrestrial civilizations, and the physical fate of the universe. These topics have major implications for our thinking and action on sustainability. While we may not be doomed, we must take certain actions to sustain ourselves in this universe. The topics also suggest that our current sustainability efforts may be of literally galactic importance.