This month’s Scientific American has an interesting one-page article on sunspots. The 11-year cycle (the Schwabe cycle) is the one we tend to focus on, but there are 88 year cycles (the Gleissberg), occasional 200 year peaks (Suess-DeVries), and a 2,400 year (Hallstatt) cycle as well. The longer cycles look like modulation envelopes with the shorter cycles constrained within them.
It seems from the graphic that we are only a few hundred years off the low of the 2,400 year cycle as well as suffering the bottom of the 11 year. The last peak of the 2,400 year looks like it was at about the year 300 CE (a/k/a AD). So the next Hallstatt peak should be due in around 600 years, if I am interpolating from the graphics correctly. I should probably replace all the coax by then. The article is non-technical but visually striking. I have no way to post it, and shouldn’t without SA’s permission anyway; but I can send a pdf copy by return e-mail attachment if anyone wants one. Request off line please since this is sort of OT. Ted, KN1CBR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
