In a dingy apartment building, insulated by layers of hanging rugs, the last family on Earth huddles around a fire, melting a pot of oxygen. Ripped from the sun’s warmth by a rogue dark star, the planet has been exiled to the cold outer reaches of the solar system. The lone clan of survivors must venture out into the endless night to harvest frozen atmospheric gases that have piled up like snow.

As end-of-humanity scenarios go, that bleak vision from Fritz Leiber’s 1951 short story “A Pail of Air” is a fairly remote possibility. Scholars who ponder such things think a self-induced catastrophe such as nuclear war or a bioengineered pandemic is most likely to do us in. However, a number of other extreme natural hazards—including threats from space and geologic upheavals here on Earth—could still derail life as we know it, unraveling advanced civilization, wiping out billions of people, or potentially even exterminating our species.

To read more, click here.