Our nearest star, the Sun.

After 10 years absence I started again with the daily Sunspot count from the middle of June weather permitting. But also time is needed during the day. That is why I think there are so few Sunspot observers around. It is the perfect job for the Amateur who is on pension or who works shifts, and also those who work from home.

I use a Herschel wedge which is very safe to use and is not widely known surprisingly. It is best to use on a Refractor. That is the only instrument I used all the time. If you want to use a Reflector for Sunspot counting it is better to put a Mylar sheet over the tube's front opening. I am not sure if the secondary mirror can survive the heat from the concentration of the Sun's rays before it is directed to the eyepiece.

Next time I will explain how a Herschel wedge works.

Here is some data of Sunspots as seen from Edenvale in Gauteng S.A. with a Refractor of 50mm aperture ( 2 inch ). June 2000 beginning on the 18th, with 9 groups and 76 spots, seeing conditions were not too bad. It was fairly steady during the rest of the month with the highest count on 29 June, 12 groups and 66 spots. The lowest count was on 24 June, with 8 groups and 36 spots.

July 2000 was at times wild. First count on 3 July 10 groups and 42 spots. 7 July the spots count went up dramatically with 6 groups and 106 spots. The highest count of the month was 22 July with 13 groups and 162 spots! The lowest was 31 July with 7 groups and 31 spots.

When you count Sunspots, you first make a drawing of the disc on paper and then draw with a pencil the spots according to what you see on the sun. I use a little notebook one page

 after the other so you can see nicely how the spots grow and disappear as well as the rotation of the Sun. It also helps you to look for spots in places where there is at first nothing to be seen but the day before there were spots. There is than more moisture in the air above with the seeing not too good. After a little bit of good looking it is amazing how the spots are suddenly seen.

August 2000 was a bit more modest with on 1 August 8 groups and 29 spots. The highest count was 7 August with 14 groups and 58 spots. Lowest count was 22 August with 4 groups and 19 spots.

September 2000 started off with 7 groups and 31 spots on the 2nd of September. Highest count for the month was 24 September with 6 groups and 134 spots. In the middle of the disc was one huge group with 74 spots alone. Left of this group another with 39 spots. The lowest count for the month was 11 Sept. with 1 group and 2 spots. But the seeing on that day was poor so there could have been more.  

October 2000 I only managed to take 7 counts. 6 October started with 7 groups and 30 spots. Highest was 13 October with 8 groups and 60 spots. Lowest count was on 14 October with 4 groups and 31 spots. Here we see a dramatic change in spot numbers in one day. The change is due to the Sun rotation, changing seeing conditions and also spots disappearing and spots appearing.

The picture is never the same - it stays interesting, one always wondering what next is to be seen.

Happy observing till next time.

Frans van Nieuwkerk.