Habitable Zone
The range of orbital distances where liquid water could exist on a planet's surface.
Also: Goldilocks zone · CHZ
Definition
The habitable zone (also called the Goldilocks zone) is the range of orbital distances from a star within which a rocky planet with an appropriate atmosphere could maintain liquid water on its surface—a key requirement for life as we know it. The zone's extent depends on stellar luminosity and is not a guarantee of habitability, as atmospheric composition, geology, and magnetic fields also play important roles.
Example
“Earth orbits comfortably within the Sun's habitable zone, maintaining average surface temperatures of about 15 degrees Celsius that allow liquid water oceans; Mars lies at the outer edge and is too cold, while Venus is inside the inner edge and too hot.”
Synonyms
- Goldilocks zone
- circumstellar habitable zone
- life zone
Antonyms / Opposites
- uninhabitable zone
Images
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Related Terms
- Exoplanet
- Stellar Evolution
- Atmosphere
- Astrobiology