<p>For stars, field rotation can be accounted for with an equatorial mount aligned with the Earth's axis and turning at the correct rate.</p>

<p>Since the Moon's orbit is on a different axis then the Earth's rotation it seems like the Moon's own motion would also contribute to field rotation with respect to the observer. </p>

<p>Is this correct? For instance, would pictures taken on a properly aligned equatorial mount still appear rotated to each other over time?</p>

<p>How would we find the field rotation due to this?</p>

CC BY-SA 4.0
2020-02-18T22:17:14.923Z
Is it really the rotation of the Moon's disk *relative to the field of stars* that you are asking about, rather than "field rotation"? It's an interesting question, the Moon does quite a dance with rect to it's center [as shown here](https://space.stackexchange.com/q/19936/12102), and the speed and direction of the motion of its center relative to the stars varies as well.
uhoh
CC BY-SA 4.0
2020-02-18T22:22:46.310Z
@uhoh I mean with respect to the observer. For instance, if you photographed the moon with an equatorial mount, would you still see rotated images over some period of time.
jeffry7
CC BY-SA 4.0
2020-02-19T10:28:33.750Z
If you mean the moon won't be fixed on your frame than yes.
Alchimista
CC BY-SA 4.0
2020-02-19T10:56:24.227Z
Fortunately, long duration exposures of the moon are not required and so the rotation, and drift eastwards, are not a proble in practice.
Dr Chuck
<the-moon><observational-astronomy>
Field rotation and observing the moon
jeffry7
# Field rotation and observing the moon

(Asked by: username_0 on 2020-02-18)

For stars, field rotation can be accounted for with an equatorial mount aligned with the Earth's axis and turning at the correct rate.

Since the Moon's orbit is on a different axis then the Earth's rotation it seems like the Moon's own motion would also contribute to field rotation with respect to the observer.

Is this correct? For instance, would pictures taken on a properly aligned equatorial mount still appear rotated to each other over time?

How would we find the field rotation due to this?

**Tags:** the-moon, observational-astronomy
> **Comments:**
> **username_1**: Is it really the rotation of the Moon's disk *relative to the field of stars* that you are asking about, rather than "field rotation"? It's an interesting question, the Moon does quite a dance with rect to it's center [as shown here](https://space.stackexchange.com/q/19936/12102), and the speed and direction of the motion of its center relative to the stars varies as well.  
> **username_0**: @uhoh I mean with respect to the observer. For instance, if you photographed the moon with an equatorial mount, would you still see rotated images over some period of time.  
> **username_2**: If you mean the moon won't be fixed on your frame than yes.  
> **username_3**: Fortunately, long duration exposures of the moon are not required and so the rotation, and drift eastwards, are not a proble in practice.  

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