October’s Giant Sunspot

This image of the Sun was captured at 3 p.m., PDT, on October 21. Courtesy Gary Seronik — This image of the Sun was captured at 3 p.m., PDT, on October 21. (Gary Seronik)

In late October, an enormous sunspot made its way across the solar disc. It was big enough to be seen “naked eye” with appropriate protection, such as solar eclipse glasses. Indeed, the spot was possibly the biggest one to appear yet in the current solar cycle! In a small telescope the group (designated AR2192) showed all kinds of intricate detail.

Seronik-Oct23-14-eclipse — The sunspot added extra interest to the October 23 partial solar eclipse. (Gary Seronik)

Mike Wirths captured this view of the sunspot group on October 21. His image was taken in Hydrogen-alpha light with a Lunt 6-inch solar refractor from northern Baja California. — View of the sunspot group on October 21 taken in Hydrogen-alpha light with a Lunt 6-inch solar refractor from northern Baja California. (*Mike Wirths*)

The Sun undergoes an 11-year cycle, during which the number of sunspots climbs to a peak before settling down for solar minimum. But not all solar maximums are created equal — even the cycle’s duration can vary from nine to fourteen years. The relative quiet of the current cycle (cycle 24) is likely a feature of normal, long-term variations. According to Dean Pesnell of the Goddard Space Flight Center, and key member of the NOAA/NASA Solar Cycle Prediction Panel, the long awaited peak of the current solar cycle finally arrived this past summer. That means, in theory at least, we should begin to see a gradual decline in the number of sunspots.