<p>Jean Meeus, in his excellent <em>Mathematical Astronomy Morsels</em>, p. 91, says:</p>
<blockquote>
<p>We then, finally, obtain the following mean frequencies for any given point at the Earth’s surface:<br>
  a total eclipse once in 375 years,<br>
  an annular eclipse once in 224 years,<br>
which, by combination, gives an annular <em>or</em> a total eclipse every 140 years for a place chosen at random. Because our results are based on a sample of observable eclipse, they are subject to uncertainty of about 16 years’ standard error for total eclipses, 7 years for annular, and 4 years for both. Further error may arise because of the limited number of points on the Earth’s surface used in the analysis.</p>
</blockquote>
<p>(emphasis in original)</p>
<p>He also points out that this is an <em>average</em> and that some places sometimes get to see two eclipses in a much shorter time (barely more than 9 years between the eclipses of May 2142 and June 2151 for Antwerp [Belgium]).</p>

CC BY-SA 4.0
2023-12-09T13:50:29.607Z
Including Lunar and partial eclipsies would make this much less,  I'd guess that the total eclipse are just a rounding error compared to the frequency of partial solar and lunar eclipies.
James K
CC BY-SA 4.0
2023-12-09T14:11:41.933Z
Including lunar eclipses, we get approximately one eclipse every two or three years, if I remember correctly.
Pierre Paquette
CC BY-SA 4.0
2023-12-10T15:38:48.580Z
My question was what is if we include **partial** eclipses, not just annular (But I didn't asked to include solar and lunar eclipses in the same calculation).
George Lee
CC BY-SA 4.0
2023-12-10T15:44:14.270Z
As for the shortest time between two total/annular eclipses, it's 6 months, as I stated in my question, see https://texashighways.com/travel/the-science-and-luck-of-the-two-upcoming-eclipses-in-texas/. But I'm not sure if this still holds if we exclude annular eclipses.
George Lee
CC BY-SA 4.0
2023-12-09T09:59:24.227Z
2023-12-09T09:59:24.227Z
Pierre Paquette
<p>There are dozens of places where you can see how often <strong>total</strong> eclipses occur at the same location <strong>on average</strong>. My question is, how often do eclipses occur at any given place, if we include partial eclipses (but not penumbral lunar eclipses)? Which includes:</p>
<ul>
<li>What is the average time between two solar eclipses <strong>of any type</strong> (at a given place)?</li>
<li>What is the most time between two solar eclipses of any type?</li>
<li>What is the average time between two lunar eclipses <strong>including partial eclipses</strong>?</li>
<li>What is the most time between two lunar eclipses including partial eclipses?</li>
</ul>
<p>And even when it comes to total eclipses, no one bothered to talk about the extremes. So</p>
<ul>
<li>What is the most time between two total lunar eclipses?</li>
<li>What is the most time between two total solar eclipses?</li>
</ul>
<p>OK, for this one I guess the answer isn't available, see <a href="https://astronomy.stackexchange.com/questions/50993/counting-from-the-21st-century-forward-what-place-on-earth-will-be-last-to-expe">Counting from the 21st century forward, what place on Earth will be last to experience a total solar eclipse?</a>.</p>
<p>The reason I'm not asking about the <em>least</em> time between eclipses is, that after a quick look on eclipse lists it's obvious that any kind of eclipse(not taking in account penumbral lunar eclipses) can repeat after six months.</p>

CC BY-SA 4.0
2023-12-09T03:17:43.977Z
I don't have much of a reference, but a slide deck I have says it's about once every 400 years.
Greg Miller
CC BY-SA 4.0
2023-12-10T15:33:22.383Z
@GregMiller Not clear to what you refer.
George Lee
<solar-eclipse><lunar-eclipse>
How often do eclipses occur at any given place, if we include partial eclipses?
George Lee
# How often do eclipses occur at any given place, if we include partial eclipses?

(Asked by: username_0 on 2023-12-08)

There are dozens of places where you can see how often **total** eclipses occur at the same location **on average**. My question is, how often do eclipses occur at any given place, if we include partial eclipses (but not penumbral lunar eclipses)? Which includes:

* What is the average time between two solar eclipses **of any type** (at a given place)?
* What is the most time between two solar eclipses of any type?
* What is the average time between two lunar eclipses **including partial eclipses**?
* What is the most time between two lunar eclipses including partial eclipses?

And even when it comes to total eclipses, no one bothered to talk about the extremes. So

* What is the most time between two total lunar eclipses?
* What is the most time between two total solar eclipses?

OK, for this one I guess the answer isn't available, see [Counting from the 21st century forward, what place on Earth will be last to experience a total solar eclipse?](https://astronomy.stackexchange.com/questions/50993/counting-from-the-21st-century-forward-what-place-on-earth-will-be-last-to-expe).

The reason I'm not asking about the *least* time between eclipses is, that after a quick look on eclipse lists it's obvious that any kind of eclipse(not taking in account penumbral lunar eclipses) can repeat after six months.

**Tags:** solar-eclipse, lunar-eclipse

> **Comments:**
> **username_1**: I don't have much of a reference, but a slide deck I have says it's about once every 400 years.  
> **username_0**: @GregMiller Not clear to what you refer.  

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## 1 answers

### Answer by username_2 on 2023-12-09. Score: 1

Jean Meeus, in his excellent *Mathematical Astronomy Morsels*, p. 91, says:

> We then, finally, obtain the following mean frequencies for any given point at the Earth’s surface:  
>   a total eclipse once in 375 years,  
>   an annular eclipse once in 224 years,  
> which, by combination, gives an annular *or* a total eclipse every 140 years for a place chosen at random. Because our results are based on a sample of observable eclipse, they are subject to uncertainty of about 16 years’ standard error for total eclipses, 7 years for annular, and 4 years for both. Further error may arise because of the limited number of points on the Earth’s surface used in the analysis.

(emphasis in original)

He also points out that this is an *average* and that some places sometimes get to see two eclipses in a much shorter time (barely more than 9 years between the eclipses of May 2142 and June 2151 for Antwerp [Belgium]).

> **Comments:**
> **username_3**: Including Lunar and partial eclipsies would make this much less,  I'd guess that the total eclipse are just a rounding error compared to the frequency of partial solar and lunar eclipies.  
> **username_2**: Including lunar eclipses, we get approximately one eclipse every two or three years, if I remember correctly.  
> **username_0**: My question was what is if we include **partial** eclipses, not just annular (But I didn't asked to include solar and lunar eclipses in the same calculation).  
> **username_0**: As for the shortest time between two total/annular eclipses, it's 6 months, as I stated in my question, see https://texashighways.com/travel/the-science-and-luck-of-the-two-upcoming-eclipses-in-texas/. But I'm not sure if this still holds if we exclude annular eclipses.  

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