The Sunspots Are Coming!
by Ron Chester ★ Sunday, December 13, 2020

Sunspot Cycle #24 recently ended, having peaked with a sunspot number of 116, not so hot for DXers.  NASA and NOAA have already predicted that Cycle #25, just beginning, will likely be as weak as #24.  

But WAIT, there is more. The National Center for Atmospheric Research (NCAR) is predicting that Cycle #25 could be one of the strongest since record-keeping began, peaking at 210 to 260 sunspots. That's a big difference of opinion!  

Should we care? If we want to have tons of fun easily working DX all over the world in the new cycle, then yes, we're hoping that NCAR is right. I have been in ham radio during all of the previous five solar cycles. I was first licensed in 1960, which was during the cycle just before those, which had by far the most sunspots in my lifetime. If you look at the graphs of the last six sunspot cycles, the biggest one by far, peaked around 1958-59 with more than 350 sunspots!  So I missed the best of that one by about two years. The five cycles since then all peaked far lower, with only two of them peaking at more than 250 sunspots. My Elmer (W0RJW) got started in ham radio a few years before me. So he had his general class ticket thoughout the peak of that monster cycle. He told me he would rush home from school so he could get on the air and work tons of DX in the mid to late afternoon. The conditions during those years are legendary among hams who were able to enjoy them.  

Recently published is a dramatic image of one of these sunspots, photographed on 29 January 2020 by a new telescope on Maui in Hawaii. This is what we need. More of those!


Yearly mean sunspot numbers, 1700 to 2014. Note especially 1956 to 1959. Or as graphed.

Propagation tutorial. A very good simple summary. WM7D solar resource page.

I get the SFI, A index and K index from the Propagation Now section of DX Summit.