circumstellar habitable zone
Sign in to savezone around the star with strong possibilities for stable liquid water and evolution of life
AI overview
A circumstellar habitable zone is the region around a star where conditions are right for liquid water to exist on a planet's surface—not so close that it boils away, and not so far that it freezes. This zone matters because liquid water is essential for life as we know it, making it the primary target in our search for planets where life could potentially develop.
AI-generated from the Wikipedia summary — may contain errors.
Article
A diagram depicting habitable zone boundaries across star type with December 2025 data. Earth is plotted alongside 45 exoplanets with radii less than 2 times that of Earth or masses less than 5 times that of Earth, making them potentially rocky worlds in the habitable zone.
In astronomy and astrobiology, the habitable zone (HZ), also known as the circumstellar habitable zone (CHZ), or as the Goldilocks zone, is the range of orbits around a star within which a planetary surface could potentially support liquid water. Liquid water is considered by many scientists as necessary for a planet to be habitable. The range depends upon the brightness of the star interacting with a planet's atmosphere. At the inner edge the star's light, trapped by greenhouse gases in a planet's atmosphere, boils off the planet's water. At the outer edge light from the star is insufficient even with help from atmospheric gas and the planet's water freezes. Many other factors are added in various habitable zone models. The habitable zone has become a key tool in the search for habitable planets because discoveries of exoplanets yield approximate orbital radii.