Why Does the Same Side of the Moon Always Face the Earth?

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One Moon “day” is approximately 29 1/2 Earth days. This rotation coincides with its orbit around the Earth so that we only see about 59% of the surface of the Moon from Earth. When the Moon first formed, its rotational speed and orbit were very different than they are now. Over time, the Earth’s gravitational field gradually slowed the Moon’s rotation until the orbital period and the rotational speed stabilized, making one side of the Moon always face the Earth.

[Honr]

If we're really quiet, we can hear a flat earther's brain burst into flames.

[jasonblack]

"You'll be dead a very very long time " had me on the floor lmao

[hkitm]

"Why Does the Same Side of the Moon Always Face the Earth?" So UFOnauts can hide on the far side!

[anzaca]

Who needs a 7 minute video to answer such a simple question? The moon's orbital and rotational periods are the same, due to tidal locking.

[SkylerKing]

Well, hello existential crisis. I wasn't expecting to meet you, here.

[reddog-exdx]

"There is no dark side of the moon. As a matter of fact, it's all dark." Where's the cheese?

[foureyedchick]

This is an excellent explanation. I can see how flat-earth people can state (erroneously, of course) that the moon is a flat disk glued to a dome facing us.

[Fadeddeath]

Brilliant video Simon. Funnily enough, I just brought up the Moon's slow drift away from the Earth while discussing hypotheticals with my siblings the other night. My brother asked how I know this stuff. Videos like this are one of the reasons I know stuff like this!

[montythepython]

What a wonderful fragile planet we live. Thank you Simon!!!!

[YeppyNope]

Because it's self-aware about it's "dark side"

[fhuber]

"tidal lock"

Eventually the same side of the Earth will always face the moon.

[alexlandherr]

You’re fantastic at explaining celestial mechanics on a reasonably good level.

[shinobikenobi]

Take a drink every time some smart guy comments "actually, there is no dark side of the moon, it's all dark." It's fun.

[RyanStonedonCanadianGaming]

If the movie The Time Machine serves me correct, even before a billion years Humans will be extinct and the planet of the apes would have risen and fallen and risen again.

[sarsen]

Got a tricky topic for ya: WHY does time FLY when you’re having fun?

[rayjack]

Simple question for any one that can answer: When viewing the moon from the same exact location, how has it completely rotated 180° and appears upside down in the sky? Full moon observations made in the exact same location roughly 6 months apart. Timeline: February 24, 2024-Sept 17, 2024 Location: (EST United States)

[florencegomer]

The moon orbits the Earth once every 27.5 days with respect to the background stars. As the Earth has moved part way in its orbit around the sun in that time, the moon phases take 29.5 days to complete one cycle. The stars rise about 4 minutes earlier each night, the moon rises about 50 minutes later each time.

[bradbasham]

Keith Richards will witness all of this.

[klafbang]

I learned that it is always the outside of the moon facing towards the Earth. Similarly, there's a trick to finding your way in the woods without a compass: the moss always grows on the outside of the trees.

[KEVMAN]

It's the backside of the moon that faces Earth. It's constantly mooning us.