The moon depending on where it is at your time of day can affect whether or not there’s high or low tides. Basically moving all of the water in the ocean, at least that’s how I think. But how come it doesn’t make us feel lighter or heavier throughout the day? Or just seem to affect anything else
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The strength of any body’s gravity decreases with distance, as you may know. So the Moon attracts the near side of Earth more strongly than the core, and the core more strongly than the far side. This means that the point nearest the Moon is pulled away from the Earth’s core, and the core is pulled away from the far side. This effect is obviously too weak to make much difference to the shape of the solid Earth; but water is, y’know, less rigid.
Earth inflicts tide on the Moon, too, about twenty times as strongly, and that is why the Moon (like most known moons of other planets) is stuck with one side permanently turned toward us: the tide latched onto an asymmetry in its mass distribution. The effect is even used to stabilize artificial satellites.
It doesn’t affect your body, because the distance across your body (and hence the force difference) is tiny.
Others have commented that it’s because the ocean is massive. That’s nonsense. If seawater were less dense, it would respond in the same way, just as two balls of different masses fall at the same speed.
Nor is the eccentricity of the moon’s orbit relevant much. The effect is slightly weaker when the moon is farther away, but qualitatively the same.
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