Goldilocks Zone

Demonstrate an understanding of the existence and significance of habitable zones/Goldilocks zones

The Habitable zone is an area surrounding a star in which a planet can have liquid water at its surface. If water is present, life could be too. It is sometimes known as the Goldilocks zone as it is not too hot and not too cold.

In our Solar System it is thought the zone extends from outside the orbit of Venus to halfway through the asteroid belt (0.75 to 3AU). This is dependent on certain models however. A larger star would produce a habitable zone that was further out. A smaller star would produce a nearer habitable zone.

The habitable zone is of course dependent on a planet fulfilling the criteria of having a suitable atmosphere and magnetosphere capable of keeping liquid water on its surface. It also ignores the possibility that life may exist on planets or moons beneath the surface outside of the habitable zone.

This region is also known as the CHZ (Circumstellar Habitable Zone).


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Habitable Zone

Fomalhaut - Artist impression of Exoplanet

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Sol Station Habitable Zones


- Why are scientists interested in finding Earth-like planets in the habitable zone around a star?
- Describe how the size of a star affects the potential habitable zone around a planet.

Did you know?

Scientists think that galaxies have a similar area so that only a certain region of a galaxy is capable of producing these conditions