The enormous AR1476 sunspot group has been cracking with A and C class flares over the last few days. Like AR1339 this one is visible with the (shielded) naked eye as well measuring a whopping 60,000 miles across. Have a look at the to scale image of the Earth to get an idea of just how big this really is.
The Sun has been treating us to some great activity recently. Every time one looks there are numerous sunspots, filaments and prominences. The extended minimum of 2009 (where we went 260 days without a sunspot) is now a distant memory. Is there an M class flare coming? If so maybe we will be treated to a nice bout of auroral activity. Have to keep my eyes on this one.
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.