The Growing Habitable Zone: Locations for Life Abound
By Ker Than, Staff Writer posted: 07 February 2006 06:59 am ET In a galaxy filled with billions of stars, scientists searching for alien life need some way to pick out those which are most likely to harbor habitable planets and moons. For more than 150 years, an important tool in this screening process has been the concept of a "circumstellar habitable zone."http://www.space.com/scienceastronomy/060207_habitable_zone.html