• johannesvanderwhales@lemmy.world
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    4 个月前

    As far as we know it’s extremely rare and a bit of a mystery how it came to be that way. One theory is that it was the result of a collision with another protoplanet in the early formation of the solar system.

    • JimVanDeventer@lemmy.world
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      4 个月前

      But it isn’t a mystery at all. The moon is moving away from us. For billions of years the moon’s apparent size was larger than the sun. For billions of years later it will appear smaller. It’s simply a lucky coincidence we live in this moment in time, in that regard.

      • johannesvanderwhales@lemmy.world
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        4 个月前

        The “mystery” I was referring to was how we came to have such a large moon to begin with. It’s very unusual, and moons on other terrestrial planets are much smaller and probably formed through completely different ways than earth’s moon.

        • JimVanDeventer@lemmy.world
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          4 个月前

          That isn’t clear at all and I’m not even sure I agree, regardless. Hydrostatic equilibrium is a regularly occuring thing. No, I’m not looking up how regular. The Universe is mind-bogglingly enormous and everything is unusual. Have a good day.

      • Melatonin@lemmy.dbzer0.com
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        4 个月前

        I really think we should be called a twin planet system. It would be much more representative of our relationship with our satellite.