<p>They are not real. </p>

<p>The images used in the animation use a mosaic of photographs taken by an orbiting satellite, the <a href="https://en.wikipedia.org/wiki/Clementine_(spacecraft)">Clementine orbiter</a>. This satellite has a polar orbit, and so returns images in strips that run roughly north-south. Due to variations in lighting between orbits, when the strips are joined together, there are artefacts at the joins.</p>

<p>The whole moon image from a ground-based telescope doesn't have such artefacts. The lunar orbiter view was used as it covers the whole moon, including the far-side. As the moon orbits Earth, it appears to wobble (an effect known as libration.) By starting with a whole moon map, and then projecting it to a sphere, this libration can be simulated. You couldn't do that with a single ground-based image.</p>

CC BY-SA 3.0
2017-01-28T08:43:32.210Z
It does have that "freshly mowed lawn" look to it. Ah yes, I can [see it here, clearly](https://astrogeology.usgs.gov/search/map/Moon/Clementine/UVVIS/Lunar_Clementine_UVVIS_WarpMosaic_5Bands_200m). While the [periapsis](http://nssdc.gsfc.nasa.gov/planetary/clementine.html) toggled between about 28 degrees north and south, the inclination was 90 degrees (polar). If you know more about this November 2007 animation (not the September 2005 in Wikipedia), I've [asked further](http://space.stackexchange.com/q/19936/12102) about the animation.
uhoh
CC BY-SA 3.0
2017-01-28T07:27:10.857Z
2017-01-28T11:13:40.197Z
2017-01-28T11:13:40.197Z
James K
<p>In <a href="https://space.stackexchange.com/q/19936/12102">this question</a> I mention the GIF in EarthSky.org's Moon Phases update <a href="http://earthsky.org/astronomy-essentials/lengths-of-lunar-months-in-2017" rel="nofollow noreferrer">Lengths of lunar months in 2017</a>. After watching it a while, I've noticed a pattern of parallel nearly vertical lines on the Moon image that's used to generate this simulation. I've shown it below. However, if I look at the moon image in Wikipedia, which is much larger, higher resolution, and has perhaps higher contrast, I don't see it.</p>

<p>It could be there, but less noticable due to the enhanced level of detail i the large image, but I am wondering - is it real, or not. If not, how did it get into this image?</p>

<p><a href="https://i.sstatic.net/wstX2.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wstX2.gif" alt="enter image description here"></a></p>

<p><strong>above:</strong> Animation used in <a href="https://space.stackexchange.com/q/19936/12102">EarthSky.org</a>.</p>

<p><a href="https://i.sstatic.net/AXqTC.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/AXqTC.png" alt="enter image description here"></a></p>

<p><strong>above:</strong> Frame 29 from the GIF Animation used in <a href="https://space.stackexchange.com/q/19936/12102">EarthSky.org</a>.</p>

<p><a href="https://i.sstatic.net/NGil0.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/NGil0.png" alt="enter image description here"></a></p>

<p><strong>above:</strong> A casual analysis of the cropped ROI. The traces are color: top, middle, and bottom third, column averages, black: entire column average. Short vertical lines are drawn by hand to try to point out the pattern that I'm seeing.</p>

<p><a href="https://i.sstatic.net/vanMZ.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/vanMZ.jpg" alt="enter image description here"></a></p>

<p><strong>above:</strong> "Full Moon photograph taken 10-22-2010 from Madison, Alabama, USA. Photographed with a Celestron 9.25 Schmidt-Cassegrain telescope..." from <a href="https://en.wikipedia.org/wiki/File:FullMoon2010.jpg" rel="nofollow noreferrer">here</a>.</p>

CC BY-SA 3.0
2017-01-28T08:48:01.750Z
I've updated to the correct link for the EarthSky article where I originally found the GIF
uhoh
<the-moon><surface>
Are these parallel lines I'm seeing in this image a real pattern on the Moon?
uhoh
# Are these parallel lines I'm seeing in this image a real pattern on the Moon?

(Asked by: username_0 on 2017-01-28)

In [this question](https://space.stackexchange.com/q/19936/12102) I mention the GIF in EarthSky.org's Moon Phases update [Lengths of lunar months in 2017](http://earthsky.org/astronomy-essentials/lengths-of-lunar-months-in-2017). After watching it a while, I've noticed a pattern of parallel nearly vertical lines on the Moon image that's used to generate this simulation. I've shown it below. However, if I look at the moon image in Wikipedia, which is much larger, higher resolution, and has perhaps higher contrast, I don't see it.

It could be there, but less noticable due to the enhanced level of detail i the large image, but I am wondering - is it real, or not. If not, how did it get into this image?

[![enter image description here](https://i.sstatic.net/wstX2.gif)](https://i.sstatic.net/wstX2.gif)

**above:** Animation used in [EarthSky.org](https://space.stackexchange.com/q/19936/12102).

[![enter image description here](https://i.sstatic.net/AXqTC.png)](https://i.sstatic.net/AXqTC.png)

**above:** Frame 29 from the GIF Animation used in [EarthSky.org](https://space.stackexchange.com/q/19936/12102).

[![enter image description here](https://i.sstatic.net/NGil0.png)](https://i.sstatic.net/NGil0.png)

**above:** A casual analysis of the cropped ROI. The traces are color: top, middle, and bottom third, column averages, black: entire column average. Short vertical lines are drawn by hand to try to point out the pattern that I'm seeing.

[![enter image description here](https://i.sstatic.net/vanMZ.jpg)](https://i.sstatic.net/vanMZ.jpg)

**above:** "Full Moon photograph taken 10-22-2010 from Madison, Alabama, USA. Photographed with a Celestron 9.25 Schmidt-Cassegrain telescope..." from [here](https://en.wikipedia.org/wiki/File:FullMoon2010.jpg).

**Tags:** the-moon, surface

> **Comments:**
> **username_0**: I've updated to the correct link for the EarthSky article where I originally found the GIF  

---

## 1 answers

### Answer by username_1 on 2017-01-28. Score: 15 | Accepted answer

They are not real.

The images used in the animation use a mosaic of photographs taken by an orbiting satellite, the [Clementine orbiter](https://en.wikipedia.org/wiki/Clementine_(spacecraft)). This satellite has a polar orbit, and so returns images in strips that run roughly north-south. Due to variations in lighting between orbits, when the strips are joined together, there are artefacts at the joins.

The whole moon image from a ground-based telescope doesn't have such artefacts. The lunar orbiter view was used as it covers the whole moon, including the far-side. As the moon orbits Earth, it appears to wobble (an effect known as libration.) By starting with a whole moon map, and then projecting it to a sphere, this libration can be simulated. You couldn't do that with a single ground-based image.

> **Comments:**
> **username_0**: It does have that "freshly mowed lawn" look to it. Ah yes, I can [see it here, clearly](https://astrogeology.usgs.gov/search/map/Moon/Clementine/UVVIS/Lunar_Clementine_UVVIS_WarpMosaic_5Bands_200m). While the [periapsis](http://nssdc.gsfc.nasa.gov/planetary/clementine.html) toggled between about 28 degrees north and south, the inclination was 90 degrees (polar). If you know more about this November 2007 animation (not the September 2005 in Wikipedia), I've [asked further](http://space.stackexchange.com/q/19936/12102) about the animation.  

---

