Irregular sun: Bob Zimmerman

May 13, 01:35 AM


(Photo: ALMA observes a giant sunspot at 1.25 mm wavelength[15])

Twitter: @BatchelorShow

Irregular sun: Bob Zimmerman

Sunspot update for April 2018: Heading into solar minimum May 7, 2018 at 9:00 am Robert Zimmerman

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for April 2018. Below is my annotated version of that graph.

While there was an uptick in sunspots in April, compared to the almost complete inactivity in March (the least active month for sunspots in a decade), the uptick did little to change the general trend. Sunspot activity is now comparable to what we saw in early 2008 (as indicated by the yellow line). This was just before the arrival of the previous solar minimum, which happened to also be one of the longest and deepest on record.