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"Claud" (2018-11-23)

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What do you do for a living? coreg cr 40 mg coupon So how did scientists come up with this number? They first looked at what defines a habitable zone in a solar system. Planets are considered habitable when they have liquid water, which is considered the keystone of life. Liquid water only forms on planets that sit within a certain zone around its star. As habitable zones change due to stars evolving over time, a planet can get pushed out of the zone. If it ends up too far away, its water becomes ice. If itâs pushed too close to the star, the water vaporizes.

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