What would the climate of the moon be like if it were big enough to have an atmosphere?

Suppose we had reached the moon and found it to be habitable. It was big enough to support an atmosphere, albeit a thinner one than the Earth has, and at some point in the past few hundred million years, was seeded with Earth-originating algae and bacteria that were ejected from the atmosphere after a large asteroid or comet impacted the Earth. In addition, our larger moon has maintained a liquid core and possesses a magnetosphere to provide some protection for its atmosphere against the solar wind.

Our hypothetical life-supporting moon is still tidally locked with Earth, and orbits at about the same distance. Based on this information, can we say roughly what the climate of the moon would be like? Obviously, the climate on the moon will vary based on location, but on average, how will it differ from the climate of Earth? Hotter? Cooler? Drier? Windier? Or, despite its larger atmosphere, will the conditions of the moon still result in the extinction of the microbes that have found their way there, resulting in a lifeless, but gassy, ball of rock?

posted about 8 years ago

ckersch‭

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