<p>In the above plot by Hathaway,
the jagged line peaking at 284.5 in June 1989
is the monthly international sunspot number.
The smooth curve starting and ending a few years later is a
<a href="https://solarscience.msfc.nasa.gov/predict.shtml" rel="nofollow noreferrer">prediction</a>
based on recent observations and statistics of past cycles.</p>

<p>The peak of 212.5 in November 1989 is for a
<a href="http://sidc.be/silso/node/52" rel="nofollow noreferrer">13-month smoothing</a>
of the monthly number.
The Sunspot Index and Long-term Solar Observations (SILSO)
project at the Royal Observatory of Belgium
<a href="http://sidc.be/silso/datafiles" rel="nofollow noreferrer">archives</a>
these data and provides
<a href="http://sidc.be/silso/monthlyssnplot" rel="nofollow noreferrer">this plot</a>
of the monthly and smoothed sunspot numbers together.
<img src="https://i.sstatic.net/Gi6sf.png" alt="SILSO plot of monthly and 13-month smoothed sunspot numbers"></p>

CC BY-SA 3.0
2018-02-26T19:04:07.797Z
2018-02-26T19:32:35.343Z
2018-02-26T19:32:35.343Z
Mike G
<p>What do the lines in this NASA graphic represent?</p>

<p>Why does Solar cycle 22 have a peak of nearly 300 (assuming that peak represents the maximum observations at the same time) and <a href="https://en.wikipedia.org/wiki/Solar_cycle_22" rel="nofollow noreferrer">this link</a> says the peak is 212)?</p>

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

CC BY-SA 3.0
2018-02-26T12:34:17.393Z
No, its not. The official number of maximum sunspots observed in Cycle 22 are 212 (see the link above) and the graph show something up to almost 300. That is my question. What is almost 300?
Max
CC BY-SA 3.0
2018-02-26T14:13:49.200Z
The white, smoothed curve looks like the smoothed variant of the white spiky curve. White and spiky goes near 300, white and smooth goes near 212 (more like 220). The error envelope of the smoothing is the white dashed.
AtmosphericPrisonEscape
<the-sun>
What are the lines in this Solar Cycle graph?
Max
# What are the lines in this Solar Cycle graph?

(Asked by: username_0 on 2018-02-26)

What do the lines in this NASA graphic represent?

Why does Solar cycle 22 have a peak of nearly 300 (assuming that peak represents the maximum observations at the same time) and [this link](https://en.wikipedia.org/wiki/Solar_cycle_22) says the peak is 212)?

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

**Tags:** the-sun
> **Comments:**
> **username_0**: No, its not. The official number of maximum sunspots observed in Cycle 22 are 212 (see the link above) and the graph show something up to almost 300. That is my question. What is almost 300?  
> **username_1**: The white, smoothed curve looks like the smoothed variant of the white spiky curve. White and spiky goes near 300, white and smooth goes near 212 (more like 220). The error envelope of the smoothing is the white dashed.  

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## 1 answers

### Answer by username_2 on 2018-02-26. Score: 4 | Accepted answer

In the above plot by Hathaway,
the jagged line peaking at 284.5 in June 1989
is the monthly international sunspot number.
The smooth curve starting and ending a few years later is a
[prediction](https://solarscience.msfc.nasa.gov/predict.shtml)
based on recent observations and statistics of past cycles.

The peak of 212.5 in November 1989 is for a
[13-month smoothing](http://sidc.be/silso/node/52)
of the monthly number.
The Sunspot Index and Long-term Solar Observations (SILSO)
project at the Royal Observatory of Belgium
[archives](http://sidc.be/silso/datafiles)
these data and provides
[this plot](http://sidc.be/silso/monthlyssnplot)
of the monthly and smoothed sunspot numbers together.
![SILSO plot of monthly and 13-month smoothed sunspot numbers](https://i.sstatic.net/Gi6sf.png)


---

