Lee Billings and Caleb Scharf

Science writers Lee Billings and Caleb Scharf discuss the possibility of life elsewhere in the universe.

The age-old question of whether we're alone in the universe - or if other life forms thrive among the stars - gets a brand new examination from science writer Lee Billings through his book, Five Billion Years of Solitude. In this critically-acclaimed volume, Lee charts the history of man's quest to determine what other Earth-like planets may exist in the universe.

Joining Lee for the evening will be Caleb Scharf, director of the Columbia Astrobiology Center at Columbia University. Caleb is the author of Gravity's Engines: The Other Side of Black Holes, and is the winner of the 2011 Chambliss Astronomical Writing Award as well as a medal from the American Astronomical Society. His blog on Scientific American is called Life, Unbound.