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Butterflydiagrams of the Sun

Since 1976 I observe the Sun systematicly. With every observation I also count the number of sunspots and do I make an exact positiondrawing. From 1980 this happens with a 90mm/f1300mm refraktor. The drawings are 150 mm in diameter with an accuracy of 99%. This means that the drawaccuracy on the centre of the sundisk is secure within 1 heliographical degree. A computer is used for storing and computing this data. So it's possible to make a butterflydiagram. In a butterflydiagram the average latitude of the leading- and following sunspots from appearing groups of sunspots is shown through the time. It looks like that at the beginning of the solarcycle sunspots are appearing at higher latitudes on the solardisk. When the cycle goes further the sunspots occurs more and more closer to the Sunequator. When a diagram is made of all of this positions it looks like a butterfly. The first observations with accurate positions were made in 1750. From 1854 every cycle got a number. The first "butterfly" in the diagram below is from 1980 and has number 21. The now disappearing sunspotscycle is the 23th. The first sunspots from the 24th cycle will come up some years later! The most sunspots which are now appaering are mostly situated near the Sun's equator. In the long-period picture You can see that the cycle 23 is now on it's end. Complex groups to from McIntosch scale "E" or "F" are rarely visible from now on, but the solar maximum holds long this time. Now in June 2002 there are still lots of sunspots visible on the solar disk! To find out when the new solar-cycle has started you have to look at the polarities of the sunspots. This tell us of a sunspotgroup belongs to the new started cycle or not. The polarity from sunspots of the new cycle are the opposit of the old ones. In this unique site you find two butterflydiagrams of the sun:

1. View of the last 37 years

2. Butterflydiagram of the last year

Diagrams with counted number of sunspots

Here You can find some diagrams with counted sunspots through the years

-Meer over zonnepanelen

Publiekssterrenwacht "Schothorst"

-More about actual Sunobservations look here

-More about daily magnetograms look here

More about myself:


My Name is Bob van Slooten and I live in Amersfoort, The Netherlands. I am an amateurastronomer and started the observations in 1976 at the house of my parents. In 1987 I moved to the "Schothorst" public stardome. This location allowed me to make observations through the year. I could watch the whole day if there is was a clear sky. There were normally about 250 observations possible in a year. In april 2001 I had to move to my house. (Mouth and footdisease by cows and sheep in the neighbourhood of the park) I found that the frequence of looking to the sun overthere does not differ very much. I think there are more observations possible, because don't have to travel. I can immediately watch the sun when a usefull clear spell in the clouds appears. I have a good view to the east and south sky.

-For comments or more information about this page, please E-mail me!

Reproduction is permitted if the source is mentioned.

* * * Last update: 01-02-2014 * * *

Images of the South African sky

On the the next pages You can read about a visit I've made to "Spreeufontein" observatory in South Africa. This nice Observatory which has equipment to make excellent pictures of celestial objects visible at the Southern sky. For unbelieveble pictures please click the following link in your favorite language!

-See the nice pictures of the southern Sky!
-Zie de mooie foto's van de zuidelijke hemel!

The person behind this page is against unnecessary and meaningless violence; in Dutch spoken: Ik ben tegen onnodig en zinloos geweld

ik ben tegen zinloos geweld !
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