I think the reason some people might believe this claim is because we’re taught in school that the moon’s gravity causes the tides. I think the reasoning goes, “well if the moon’s gravity can affect the tides, surely it can affect smaller things too”

  • Excel@lemmy.megumin.org
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    1 year ago

    I don’t think that last part is entirely accurate. The reason the weak gravity causes tides is actually because it’s acting over the entire ocean all at once.

    It turns out that the ocean is a bit heavy… when you add up the entire mass of all of the water, this imparts quite a substantial bit of potential energy. This can be seen as a “bulge” outward in the moon’s direction, making the planet look a little “squished”.

    If the planet were perfectly smooth, this probably would be fairly stable as the bulge wrapped around the planet… however, because we have continents and the sea floor, this movement of water crashes into the land and causes ripple effects with a huge amount of kinetic energy.

    I don’t think it would take more that a few years for this process to ramp up to our current level of tides, if there were some way of doing such a ramp up in a controlled way.