APOD 1.5

Giliese 581 g (foreground) and Giliese 581 (background)

The planet Giliese 581 g, orbiting the star Giliese 581, is the first planet discovered that is in the right zone for life. The planet's temperature is just right for liquid water to exist, resulting in the nickname "Goldilocks". The planet's very slow rate of rotation results in temperature extremes, however, with the hot side reaching 160 degrees, and the dark side reaching 25 degrees below zero. The only comfortable zone would be the sunrise area, which would be comfortable. The planet is about five times the size of Earth, and it's star is about three times the size of our sun, and expected to outlive the Sun by billions of years.