Eli5: Tidal lock of moon – I have a very specific question about how this works – please see link

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[https://moon.nasa.gov/resources/429/the-moons-orbit/](https://moon.nasa.gov/resources/429/the-moons-orbit/)

OK so here is my question: this video looks like the moon is revolving around the earth but that it is not rotating on its axis at all. The earth is doing both in the video clearly and the moon “sees” other sides of the earth – b/c the earth is rotating. How exactly is the moon rotating WITHOUT turning? I assume it is turning b/c I’ve read that it does in fact rotate but I cannot wrap my brain about how it is working – how does something turn in front of you without you ever seeing the other side of it? And if it is b/c it is turning at the exact rate as the earth, why does the moon see the other side of the earth? Why aren’t they both locked? This question has bothered me for years and I’ve watched a bunch of videos on it and I just don’t get it and I feel stupid and I promise I’m not. LOL. Please – help me understand this.

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4 Answers

Anonymous 0 Comments

>but that it is not rotating on its axis at all

Yeah, that part isn’t true. It is rotating *at the same rate that it orbits* around Earth.

>I assume it is turning b/c I’ve read that it does in fact rotate

yea.

> but I cannot wrap my brain about how it is working – how does something turn in front of you without you ever seeing the other side of it

Uh…. just walk around someone but keep facing them. You know, “circle-strafe” in gaming.

> why does the moon see the other side of the earth? Why aren’t they both locked?

Because the moon is much smaller than the Earth. The Earth, given time, would become tidally locked *to the SUN*, not the moon. The moon and the other planets do play with that.

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