The Universe - New research on habitable exoplanets

The Earth is, of course, a planet orbiting the Sun.

 
                    
Exoplanets are planets of stars other than the Sun.

There are likely to be hundreds of billions of Earth-like planets in our galaxy which might support life.



The Goldilocks Zone is a band of space where liquid water can exist.

Too near the star, or too far, is bad for life.


In the case of the Sun, Venus lies inside the inner edge of the Goldilocks Zone.


Mars lies at the outer edge.

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