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In one of the answers to an entertaining question on Physics.SE about "simple check for the global shape of the earth", there is a link to this awesome demonstration of the libration of the moon:

Animation of the moons librations

You can see the date stamp at the top that goes from Apr. 3 2007 to Apr 30 2007.

If these are real, the moon should go through its phases during the month-long time-lapse photo session, but it doesn't.

Is this animation a real-life capture or generated?

Andrew T.
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Chowzen
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    I thought this site was for asking about the validity of *notable claims*, not arbitrary interesting questions. Did anyone claim that these were real photos? It does not seem so. Any physicist would have said the same thing you mentioned: there is no full moon every day. Why is this question not off-topic then? – Szabolcs Oct 23 '18 at 15:53
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    I'm voting to close this question as off-topic because it belongs on [Astronomy.SE] –  Oct 23 '18 at 18:48
  • To be clear, my question was, ["Are these images of the moon's "libations" real?"](https://skeptics.stackexchange.com/posts/42595/revisions) Regardless of the full moon effect, "Images" may be obtained of the dark-side surface of a heavenly body. Did they use infrared? X-rays?—No, they faked it with a computer. That being said, this certainly may be "off topic," as I don't know that anyone else has wondered. But I bet some have. – Chowzen Oct 23 '18 at 21:05
  • I think the edited title has made it worse. (1) The question of whether an image is "real" always makes us stumble - it is too vague (2) I avoid "Is it X or is it Y?" questions because they often are a false dichotomy (3) "capture"? What does that even mean? – Oddthinking Oct 23 '18 at 22:12

1 Answers1

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This image is software generated, according to its Wikimedia page:

  • Own work, created with "Full Sky Observatory"
  • Source bitmap for projection from Nasa's Clementine Spacecraft

You can see some pixelization happening at the very bottom and top of the moon. Another dead giveaway is the fact that the moon in the image is full for the entire month, without any change in its shadows.

(This, of course, doesn't mean that moon librations aren't real. For a trusted source see NASA, which has a similar simulator.)

Laurel
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    Thanks, +1! To be clear, I was asking if the photos (which now are shown to *not* be photos) were real, not if *librations" themselves were real. I'm a believer. :) – Chowzen Oct 23 '18 at 06:18
  • Would it not be possible to create such an animation (with the full moon visible throughout the month) from actual captures of the moon taken using a different method than photography of (visible) light? For instance, using sound waves? – Bas Oct 23 '18 at 13:58
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    @Bas: Sound waves? In vacuum? ;-) – DevSolar Oct 23 '18 at 13:59
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    @DevSolar but maybe if _it's not a moon_... – leftaroundabout Oct 23 '18 at 14:00
  • Good point, but what about some other form of energy? Although at that point I suppose you might as well shine a bright light at the moon throughout the month... – Bas Oct 23 '18 at 14:20
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    @Bas I've got a nice, bright flash on my phone's camera. :) – Chowzen Oct 23 '18 at 14:24
  • Pictures don't have to be taken from earth's surface. – xyious Oct 23 '18 at 15:46
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    @Chowzen Illuminate the moon: Obligatory [xkcd](https://what-if.xkcd.com/13/) :-) – Peter - Reinstate Monica Oct 23 '18 at 15:52
  • @bas you can use lasers from earth, it is a common practice – Richie Frame Oct 23 '18 at 17:23
  • The "dead giveaway" was mentioned in the original question. – Barmar Oct 23 '18 at 19:00
  • DSCOVR, which is at L1 and has a camera (EPIC) that could capture the moon in constant sun light. However the moon is tidally locked to earth, so it would be shown rotating... – Coomie Oct 24 '18 at 01:21
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    @xyious: But the whole point of this animation is to show the Moon's apparent oscillation relative to the Earth. – ruakh Oct 24 '18 at 03:41
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    A third hint: The moon has vertical stripes. This happens when a large image is stitched together from many small ones, in this case taken by a satellite on a polar orbit. One can see that sometimes on Google earth, too. – sweber Oct 24 '18 at 05:15