For the first time in years we have a sunspot group that is visible to the (shielded) naked eye. AR1339 is 3 times wider than the Earth and a whopping 10 times longer. See attached photo taken in Galway on Saturday afternoon. No aurora warnings as of yet but the NOAA are estimating a 70% chance of M Class solar flares and 10% of an X class event.
Image after the break – note the size of the Earth in comparison to the group!
So what is a sunspot?
Basically this is a relatively cool area on the Sun’s surface, maybe 4000 degrees C as opposed to the surrounding areas which are a couple of thousand degrees warmer which makes them seem darker to observation. Sunspots have very very strong magnetic lines running through them. They are often associated with other solar phenomenon such as prominences, filaments, plage, solar flares and Coronal Mass Ejections (CMEs). As you’ve probably guessed from my solar gallery prominences are the phenomenon that I most like to study. See here
The Sun has an eleven year cycle of high and low Sunspot activity and we’re just entering a new period of high activity so expect to see more sunspots for the next few years – actually the last cycle was far longer than normal but that’s a different story, discussed elsehwere on this website.