Wirths-Sunspot AR1944-7Jan2014
Mike Wirths captured this view of the sunspot group on January 7 His image was taken in Hydrogen-alpha light with a Lunt 6-inch solar refractor from northern Baja, California.

Big Sunspot Report

One of the biggest sunspot groups in months recently crossed the solar disc.

Wirths-Sunspot AR1944-7Jan2014
On January 7, Mike Wirths took this image of the sunspot group in Hydrogen-alpha light with a Lunt 6-inch solar refractor from northern Baja California.

Although the Sun may be in the midst of the weakest solar cycle in a century, a very large sunspot group (number AR 1944) recently made its way across the solar disc. AR 1944 was first noted on December 31, 2013, and exited the solar disc on January 13, 2014. The group spanned an impressive 200,000 kilometres, and the umbra (the darkest region) of the biggest spot alone was considerably larger than the Earth.

Seronik-Jan4 Sun
This image of the Sun, captured on the afternoon of January 4, shows the prominent sunspot group as it made its journey across the solar disc. (Gary Seronik)

The Sun undergoes an 11-year cycle, during which the number of sunspots climbs to a peak before settling down for solar minimum. In theory, at least, solar activity is at its maximum for the current cycle right now — though sunspot numbers have been very low. Not all solar maximums are created equal, however, and the relative quiet of this one is likely a feature of normal, long-term, cycle-to-cycle variations.

Mike Wirths also imaged the sunspot group on December 31, just as it was coming into view.