Astronomers call the most promising of these places "Goldilocks planets, " because they orbit in a temperate zone not too hot and not too cold to support liquid water essential for carbon-based life as we know it.

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The site, located in the south Atlantic, is one of the least-disrupted island and marine ecosystems in the cool temperate zone.

UNESCO: World Heritage

This transboundary is located in the Central European Biogeographical Region, and is characterized by boreal coniferous forests and temperate zone deciduous forest at the junction.

UNESCO: EDUCATION