Questions tagged [sunspots]

I would like to plot a butterfly diagram. I've been looking through the SOHO archive for a table that would indicate the date and position of each sunspot, but to no avail. The closest I got was to use the archived images to create the table myself,…

How a sunspot number is calculated by an individual observer? I would like to learn how to calculate the daily number of sunspots and where to get daily input images of the Sun. I have read tens of web links and none mentioned or described any…