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Look at this huge sunspot, the largest yet of Sunspot Cycle 24! It is about the same diameter as Jupiter! Notice how tiny Earth is, in comparison. Sunspots are regions on the Sun’s photosphere, formed by the “convection” of solar plasma deep inside the Sun, causing the twisting and shifting of magnetic fields. They look like spots on the photosphere because they are cooler than their surrounding solar material, giving them their dark, blemish-like appearance.

Close-up view of NOAA Active sunspot Region AR 12192 (short: 2192)

The sunspot is the largest since November 1990, and is larger than a monster sunspot that spawned a series of major solar flares over Halloween in 2003. AR 2192 was one of the biggest observed sunspots of all time, ranking 33rd largest of 32,908 active regions since 1874, according to NASA scientists C. Alex Young and Dean Pesnell.

Interestingly, this sunspot never released any major coronal mass ejection (CME), because the magnetic fields were too strong to let any significant plasma escape! However, this sunspot group unleashed a fair number of moderate to strong x-ray flares (see one of them in this video at < http://g.nw7us.us/1s7L0vF >). All told, AR 2192 popped off 26 M-class flares, and six X-class flares! Of course, during the last sunspot cycle, Cycle 23, there were many active sunspot regions unleashing flare after flare within hours of each other. That’s typical during the active phase of most sunspot cycles. This cycle, however, is one of the weakest on record, so this large sunspot with its many flares is exciting.

A Close-up of AR 2192

Each sunspot region gets a consecutive number assigned to it by the National Oceanic and Atmospheric Administration (NOAA). This sunspot region is NOAA AR (active region) Nr. 12192 (we often drop the first digit when speaking of a sunspot, so in this case, this region was often referred to as AR 2192).

One of the many x-ray flares originating from Active sunspot Region AR 2192 – this one seen in Extreme Ultraviolet at 131 Angstroms.

This sunspot region increased the ionization of the ionosphere, creating excellent conditions on all of the high frequency spectrum (shortwave, or HF). Even ten meters was alive with world-wide propagation. And, the best news is that this provided an exciting playing field for the CQ WW SSB contest in late October, 2014.

This sunspot region has now rotated away, but may return on about 24 days.

Credit: NASA/SDO/HMI

Check out: http://SunSpotWatch.com

Get the space weather and radio propagation self-study course: http://NW7US.us/swc

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