<p>The <a href="http://en.wikipedia.org/wiki/Orbit_of_the_Moon" rel="nofollow noreferrer">orbit of the moon</a> is inclined by 5.14° to the <a href="http://en.wikipedia.org/wiki/Ecliptic" rel="nofollow noreferrer">ecliptic</a>.</p>
<p>As you may know, the ecliptic is the apparent path of the Sun across the sky, so it is also the plane of Earth's orbit around the Sun. The plane of the Moon's orbit is inclined by 5.14° to the plane of the Earth's orbit. The intersection of the two planes is a line bisecting both planes.</p>
<p><img src="https://upload.wikimedia.org/wikipedia/commons/b/b7/Eclipse_vs_new_or_full_moons%2C_detailed_annotations.svg" alt="diagram of moons tilted orbit as earth circles sun" /></p>
<p>There is also a nice picture of this at <a href="http://www.cnyo.org/tag/orbital-plane/" rel="nofollow noreferrer">http://www.cnyo.org/tag/orbital-plane/</a>. [I'll insert it here after checking the copyright]</p>
<p>So, it is only when the Earth is very near to the intersection line that an eclipse can occur, because it is only then that the Sun, Moon and Earth can be in a strait line. This occurs for slightly more than a month (called an <a href="http://en.wikipedia.org/wiki/Eclipse_season" rel="nofollow noreferrer">eclipse season</a>), twice a year.</p>
<p>Another angle comes into the picture too. The axis of the Earth is tilted, so the equator is at 23.4° to the plane of the ecliptic.</p>
<p>So, the pattern you have observed comes about because of that geometry, where mirror image eclipse paths occur about six months apart.</p>
<p>The linked pages explain a lot more of the complexities.</p>
<p>Image by Nela (nyabla.net) (with additional annotations by Onceinawhile), <a href="https://creativecommons.org/licenses/by-sa/4.0" rel="nofollow noreferrer">CC BY-SA 4.0</a>, via <a href="https://upload.wikimedia.org/wikipedia/commons/b/b7/Eclipse_vs_new_or_full_moons%2C_detailed_annotations.svg" rel="nofollow noreferrer">Wikimedia Commons</a></p>

CC BY-SA 3.0
2015-03-21T16:34:23.783Z
Cool, thanks. The picture in the article says it all.
But then it's a bit unclear why there can be 1-3 more solar eclipses per year
Actine
CC BY-SA 4.0
2015-03-21T03:45:42.600Z
2023-11-01T12:29:48.940Z
2023-11-01T12:29:48.940Z
andy256
<p>Reading upon the eclipse of March 20, 2015, I stumbled upon this page: <a href="http://www.timeanddate.com/eclipse/list-solar.html" rel="nofollow">http://www.timeanddate.com/eclipse/list-solar.html</a>. What caught my eye is that for each year there are two eclipses whose paths are almost symmetrical relative to equator.</p>

<p>I'm just curious why that's always exactly so.</p>

<solar-eclipse>
Why solar eclipse paths are symmetrical?
Actine
# Why solar eclipse paths are symmetrical?

(Asked by: username_0 on 2015-03-20)

Reading upon the eclipse of March 20, 2015, I stumbled upon this page: <http://www.timeanddate.com/eclipse/list-solar.html>. What caught my eye is that for each year there are two eclipses whose paths are almost symmetrical relative to equator.

I'm just curious why that's always exactly so.

**Tags:** solar-eclipse


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## 1 answers

### Answer by username_1 on 2015-03-21. Score: 2 | Accepted answer

The [orbit of the moon](http://en.wikipedia.org/wiki/Orbit_of_the_Moon) is inclined by 5.14° to the [ecliptic](http://en.wikipedia.org/wiki/Ecliptic).

As you may know, the ecliptic is the apparent path of the Sun across the sky, so it is also the plane of Earth's orbit around the Sun. The plane of the Moon's orbit is inclined by 5.14° to the plane of the Earth's orbit. The intersection of the two planes is a line bisecting both planes.

![diagram of moons tilted orbit as earth circles sun](https://upload.wikimedia.org/wikipedia/commons/b/b7/Eclipse_vs_new_or_full_moons%2C_detailed_annotations.svg)

There is also a nice picture of this at <http://www.cnyo.org/tag/orbital-plane/>. [I'll insert it here after checking the copyright]

So, it is only when the Earth is very near to the intersection line that an eclipse can occur, because it is only then that the Sun, Moon and Earth can be in a strait line. This occurs for slightly more than a month (called an [eclipse season](http://en.wikipedia.org/wiki/Eclipse_season)), twice a year.

Another angle comes into the picture too. The axis of the Earth is tilted, so the equator is at 23.4° to the plane of the ecliptic.

So, the pattern you have observed comes about because of that geometry, where mirror image eclipse paths occur about six months apart.

The linked pages explain a lot more of the complexities.

Image by Nela (nyabla.net) (with additional annotations by Onceinawhile), [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0), via [Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/b/b7/Eclipse_vs_new_or_full_moons%2C_detailed_annotations.svg)

> **Comments:**
> **username_0**: Cool, thanks. The picture in the article says it all. But then it's a bit unclear why there can be 1-3 more solar eclipses per year  

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