NASA | Moon Phase and Libration

The animation archived on this page shows the geocentric phase, libration, position angle of the axis, and apparent diameter of the Moon throughout the year 2011, at hourly intervals. The Current Moon image is the frame from this animation for the current hour.

This marks the first time that accurate shadows at this level of detail are possible in such a computer simulation. The shadows are based on the global elevation map being developed from measurements by the Lunar Orbiter Laser Altimeter (LOLA) aboard the Lunar Reconnaissance Orbiter (LRO). LOLA has already taken more than 10 times as many elevation measurements as all previous missions combined.

The Moon always keeps the same face to us, but not exactly the same face. Because of the tilt and shape of its orbit, we see the Moon from slightly different angles over the course of a month. When a month is compressed into 12 seconds, as it is in this animation, our changing view of the Moon makes it look like it's wobbling. This wobble is called libration.

The word comes from the Latin for "balance scale" (as does the name of the zodiac constellation Libra) and refers to the way such a scale tips up and down on alternating sides. The sub-Earth point gives the amount of libration in longitude and latitude. The sub-Earth point is also the apparent center of the Moon's disk and the location on the Moon where the Earth is directly overhead.


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[Arrowed_Sparrow]

Thank you Neil! I knew it happened, but I never thought to watch a time lapse.

[pulsartcreative]

When I'm trying to explain Lunar Libration to people - This is the video I will direct them to...Brilliant. Well done.

[jayeshchandawat]

I'm here because Neil degrasse tyson says in moon liberation, moon twerks.

[CNFrostXY]

@sarkerm2 Yes the moon rotates that is relative to all but Earth. It is locked in with Earth, hope you understand.

[asideclaro]

What? I never knew the libration was a thing? When you even look for information about lunar movements it is not usual to hear about this :o

[budrys]

Your personal movie channels cause me to feel more secure !!!

[mr_sowong]

So basically, the moon is twerking us?

[mattheweskender]

Waxing crescent, first quarter, waxing gibbous, full, waning gibbous last quarter, and waning crescent

[truvelocity]

@sarkerm2 No, that's why they say,
"he far side of the moon" - But, now we have satellites that see the other side and it looks like a human eye. Can you imagine the folklore if our civilization could have seen the other side since man existed?

[irfree]

Does this sim show the opposition surge on the lunar regolith, seen at full moon?
I see unrealistic limb darkening.

[irfree]

Can you upload a more realistic version with increased brightness, showing the earthshine around new moon and adding the opposition surge around full phase?

[shadwburnd]

One thing is certain here if any, and that is that the shadows are no longer following what this animated model is displaying herein, both in shape, direction, and fashion altogether.. I am sure with all of the preparedness videos coming out, that you guys most certainly know what the causes for everything are revolving around any mention of this subject matter.

[dakotadad]

Neil deGrasse Tyson and Cosmic queries sent me

[sarkerm]

I thought moon rotate on it's axis every month...

[MateusJaguar]

I am witnessing a change in the terminator angle from 45 degrees (the top right of the moon in half shadow to less than less than 90 degrees (the mood equally diveded left and righ but even more, the terminator gone bast equal so it is over all more than 45 degrees in 12 hours.
Can anyone explain how this is happening? I am using a telephone pole as a point of reference so I know it is not my imagination.
My smart phone is to dumb to get an image, am looking to buy something with optical zoom.

[onqproductions]

Dude, shouldn't there be a lunar eclipse at 1:05?

[gjozefi]

@ONQproductions no it's called a full moon.

[jiberish]

@losbergs2 Why are you telling me this?

[Youngblood_]

Alright... who is here because of Neil Degrasse Tyson. Lol *Keep looking up*

[AlexanderGeorge]

we see the same face of the moon.. Now i wondering(want to know) about the opposite of the moon. ^^ May be there is Auto-bots there. Sleeping.. @@