I am aware of phases and the fact that opposite sides will see the moon flipped relative to the other but what I’m asking specifically is would the almost 8000 mile difference between the two observers be enough for them to see different details near the edge of the moon?

enter image description here

So in this image, if there were 2 people on opposite sides of the earth each 90° from the person seen on top, would the person on the right see more of the right side of the moon while the one on the left couldn’t see some of that but could see more on the left?

If you have any examples of this with actual photos from each side I would love to be able to see the difference.


  • $\begingroup$ This is a great question! I've added the second part of your question back into your title so that it is now clearly not a duplicate of previous similar questions. "Would it look different" and "would photos look different" have been asked before, but specifically asking for photographic evidence in the answer Is a new question. Welcome to Astronomy SE! $\endgroup$
    – uhoh
    Jul 17, 2021 at 1:49
  • $\begingroup$ You can take both these photos yourself, just by waiting 12 hours. $\endgroup$
    – TonyK
    Jul 18, 2021 at 10:18

1 Answer 1


You are asking about the Moon's diurnal libration. While it is small (about 1°), it is easily measurable. It is also overwhelmed by the much larger librations due to the Moon's non-circular orbit and due to the Moon's orbit being inclined with respect to the Earth's equatorial plane.

  • $\begingroup$ How does the orbital inclination affect libration? $\endgroup$
    – TonyK
    Jul 18, 2021 at 10:20
  • $\begingroup$ @TonyK When the Moon's Earth-centered position is below the equator, we on Earth get to see the Moon's north pole, and points beyond on what would nominally be the far side of the Moon. The Moon's south pole is not visible at these times. The reverse happens when the Moon's Earth-centered position is above the equator. This is called libration in latitude. $\endgroup$ Jul 18, 2021 at 17:55
  • $\begingroup$ But that is because the angle between the moon's axis of rotation and its orbital plane is less than 90°. That is not what is meant by orbital inclination, which is independent of the axis of rotation. $\endgroup$
    – TonyK
    Jul 18, 2021 at 18:40

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