A newly discovered exoplanet has been moved up on the list of potential planets that may hold life because of its day/night cycle. The planet is one of six that orbits around the star HD 40307, about 42 light-years from Earth in the constellation Pictor.
The particular planet of interest is the farthest from its sun with an orbit of about 320 days, a distance that places it in the habitable zone of not too hot and not too cold. The distance is also far enough to prevent the planet from experiencing tidal locking, the quality that makes the planet more hospitable than the others in its neighborhood and than many other exoplanets. Tidal locking is the phenomenon where gravitational forces cause one side of the planet to always face its host star, like the moon to earth. Planets stuck in a tidal lock experience half of its surface in an eternal hot day and the other half in a freezing night.
Because the sixth planet orbiting HD 40307 is far enough to escape a tidal lock, it rotates the way our own Earth does with a similar day/night cycle making it much more conductive to life.
The planet is at least seven times more massive than Earth. Well, it would definitely be able to fit us if we had to flee to due to some catastrophic Earth-destroying event. Unless life is already there.