Habital zone chart

A picture of the solar system with the Habitable zone outlined in yellow.

A habitable zone, scientifically called circumstellar habitable zone (CHZ), informally Goldilocks zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.[1][2][3][4][5] The bounds of the CHZ are based on Earth's position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to Earth's biosphere, the nature of the CHZ and the objects within it may be instrumental in determining the scope and distribution of Earth-like extraterrestrial life and intelligence.

Planets within a CHZ Edit

See alsoEdit


  1. Su-Shu Huang, American Scientist 47, 3, pp. 397- 402 (1959)
  2. Dole, Stephen H (1964). Habitable Planets for Man. Blaisdell Publishing Company. p. 103. 
  3. J. F. Kasting, D. P. Whitmire, R. T. Reynolds, Icarus 101, 108 (1993).
  4. Kopparapu, Ravi Kumar (2013). "A revised estimate of the occurrence rate of terrestrial planets in the habitable zones around kepler m-dwarfs". The Astrophysical Journal Letters 767 (1): L8. doi:10.1088/2041-8205/767/1/L8. Bibcode2013ApJ...767L...8K. 
  5. Cruz, Maria; Coontz, Robert (2013). "Exoplanets - Introduction to Special Issue". Science 340 (6132): 565. doi:10.1126/science.340.6132.565. Retrieved 18 May 2013.