by Stephanie Osborn, June 7, 2017
I’ve been keeping a spreadsheet since late last summer, and here are the results, as of June 6th, 2017. (Quick and easy data source, the daily sunspot image archives from Solarham.)
This data (through March; I’ve updated it since then) was posted on Jerry Pournelle’s blog a while back, and it elicited several questions from readers, who didn’t understand the information contained therein. So here is an effort to elaborate on the data, for those of you who aren’t astronomers/ astrophysicists and don’t want to have to keep up with all this stuff.