Planet Earth is situated in what astronomers call the Goldilocks Zone -- a sweet spot in a solar system where a planet's surface temperature is neither too hot nor too cold. An ideal distance from a home star -- in Earth's case, the sun -- this habitable zone, as it is also known, creates optimal conditions that prevent water from freezing and generating a global icehouse or evaporating into space and creating a runaway greenhouse.

However, a new theory by UC Santa Barbara geochemist Matthew Jackson posits that the bulk composition of a planet may also play a critical role in determining the planet's tectonic and climatic regimes and therefore its habitability. In a paper published today in Nature Geoscience, Jackson, an associate professor in UCSB's Department of Earth Science, and Mark Jellinek of the University of British Columbia discuss their research.