Omega: The Last Days of the World is a science fiction novel by astronomer Camille Flammarion. On 25th century Earth, a comet is on a path to collide with the Earth ending it all. Astronomers predict different scenarios as to how they will all die depending on the chemical composition of the comet. Omega probes the philosophical and political consequences that arise as the human race faces the end of the world.

Urania is a work of science fiction from the fine mind of French astronomer Camille Flammarion. Named for Urania, the muse of astronomy, this book in three parts delves into philosophy, astronomy, interplanetary travel, romance, Mars, and the nature of reality. - Summary by A. Gramour