1

Counting Sunspots

Leif SvalgaardProject ASTRO

Aug. 3, 2013

2

What We are Going to Cover Today

• How to find Sunspot Drawings on the Internet

• How to Count Groups and Spots

• How to Construct Your Own Sunspot Catalog

• Making Graphs

• Historical View

• Questions & Answers

• Looking Through a Real [Modern] Telescope

3

Sunspot Drawings from Locarnohttp://www.specola.ch/e/drawings.html

Locarno, Switzerland

Click there

4

Sunspot Drawings from Locarno

Click

Click

5

This is the drawing

Click to see a larger version

Get to know his handwriting…

Groups Spots Class Latitude

R = 10*g + f = 50+28 = 78

R Wolf = 0.6 * R = 51

Marco

2

7

1

1

2

13

6

Kanzelhöhe

Locarno

Kanzelhöhe

7

11

Mt. Wilson

25 Jul

6

63

69

7

SDO/HMI

2013-Jul-26

WELocarno

SDO/HMI

Mt. Wilson

8

Enter your Estimates into a Table

SIDC [Solar Influences Data Analysis Center] is the Official Keeper of the International Sunspot Number. They produce daily [preliminary], monthly, and yearly reports and is the definitive source for Sunspot Numbers http://sidc.be/

Recall the ‘raw’ Relative Sunspot Number Definition: R = 10*groups + spots

9

Here is a chart I maintain daily

10

Counting Sunspots Only Becomes Real

Fun When You Make a Graph

0

20

40

60

80

100

120

140

160

180

200

2013.500 2013.510 2013.520 2013.530 2013.540 2013.550 2013.560 2013.570

Sunspot Numbers for July 2013

LOC

SIDC

Leif NOAA

Rudolf Wolf Alfred Wolfer

http://spaceweather.com/

You can get the NOAA sunspot number daily from

It does not have the 0.6 k-factor

0.6

11

And of Great Science Value When Graphed over Many Years (Centuries)

2009.0

Now

12

Useful and Interesting Websites

• http://sidc.be/products/meu/ • http://www.specola.ch/e/drawings.html • http://cesar.kso.ac.at/sunspot_drawings/ • ftp://howard.astro.ucla.edu/pub/obs/drawings • http://www.swpc.noaa.gov/ftpdir/indices/quar_DSD.txt • http://spaceweather.com/ • http://www.leif.org/research/ • http://www.swpc.noaa.gov/alerts/solar_indices.html• http://hirweb.nict.go.jp/sedoss/solact3 • http://wso.stanford.edu/