| Term: | Habitable zone |
| Definition: |
A zone around a star where the temperature would be in the range 0-100 °C to sustain liquid water on the surface of rocky planets (or sufficiently large moons). Water is thought to be a necessary component to the formation and evolution of Earth-type life. This zone depends on the parent star's luminosity and distance; it will be farther from hotter stars. A more accurate definition of a Habitable Zone needs to include other factors, such as orbital eccentricity, heat sources other than stellar irradiation, and atmospheric properties. |