Flexi Says: Astronomers believe that a planet must be within a certain distance from a star in order to be capable of supporting the type of life that we have on Earth, in a region known as the circumstellar habitable zone. Since planets in this zone are supposed to be not too hot and not too cold for life, it is also referred to as the "Goldilocks zone," after the famous fairy tale. It is generally regarded as the temperature range in which liquid water could exist on the surface of a planet under a range of common atmospheric pressures.
