<p>No, no such changes have been observed. Laclare et al. (1996) summarize various published solar diameter data from observations made between 1970 and 1995. Here's Figure 6 from their paper.</p>

<p><a href="https://i.sstatic.net/lan51.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/lan51.png" alt="solar diameter variations"></a></p>

<p>As you can see (and as Laclare et al. point out), solar semi-diameter has shown no significant variation during the measurement periods. Given their deviation from the other data sets, the Wittmann data seem rather suspect, but even they show absolutely no change between the 1972 and 1981 data points. In short, none of these data are consistent with the notion that solar diameter changed in 1979.</p>

<hr>

<p><strong>References</strong></p>

<p>Laclare, F., Delmas, C., Coin, J. P., &amp; Irbah, A. (1996). Measurements and variations of the solar diameter. <em>Solar Physics</em>, 166(2), 211-229.</p>

CC BY-SA 3.0
2017-08-16T22:53:13.193Z
2017-08-16T22:53:13.193Z
Pont
<p>Has been observed any changes in the real sun´s size on ocassion of the 1979 solar storm event ? (after and before)</p>

CC BY-SA 3.0
2017-08-16T21:25:37.057Z
This is a question for astronomy stack exchange, but the short answer is no, the sun is not actively changing size.  You might enjoy this site: http://solar-center.stanford.edu/FAQ/Qshrink.html
f.thorpe
CC BY-SA 3.0
2017-08-17T01:40:30.753Z
I'm in the naive category, haven't heard of this... what information has suggested to you that it might have luis?
JeopardyTempest
CC BY-SA 3.0
2017-08-17T07:30:16.260Z
I'm voting to close this question as off-topic because it belongs on Astronomy.SE
Jan Doggen
<solar-terrestrial-physics><astronomy>
Changes in Real Solar size around 1979?
luis blas Cabrera
# Changes in Real Solar size around 1979?

(Asked by: username_0 on 2017-08-16)

Has been observed any changes in the real sun´s size on ocassion of the 1979 solar storm event ? (after and before)

**Tags:** solar-terrestrial-physics, astronomy

> **Comments:**
> **username_1**: This is a question for astronomy stack exchange, but the short answer is no, the sun is not actively changing size.  You might enjoy this site: http://solar-center.stanford.edu/FAQ/Qshrink.html  
> **username_2**: I'm in the naive category, haven't heard of this... what information has suggested to you that it might have username_0?  
> **username_3**: I'm voting to close this question as off-topic because it belongs on Astronomy.SE  

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## 1 answers

### Answer by username_4 on 2017-08-16. Score: 1 | Accepted answer

No, no such changes have been observed. Laclare et al. (1996) summarize various published solar diameter data from observations made between 1970 and 1995. Here's Figure 6 from their paper.

[![solar diameter variations](https://i.sstatic.net/lan51.png)](https://i.sstatic.net/lan51.png)

As you can see (and as Laclare et al. point out), solar semi-diameter has shown no significant variation during the measurement periods. Given their deviation from the other data sets, the Wittmann data seem rather suspect, but even they show absolutely no change between the 1972 and 1981 data points. In short, none of these data are consistent with the notion that solar diameter changed in 1979.

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**References**

Laclare, F., Delmas, C., Coin, J. P., & Irbah, A. (1996). Measurements and variations of the solar diameter. *Solar Physics*, 166(2), 211-229.


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