After being asleep at the wheel the past couple months, the sun’s very much back in the game. Earlier this week, medium-class flares from two big sunspot groups made the news. Now, new sunspot group 1882, which rounded the eastern edge of the sun just yesterday, fired off not one but two powerful X-class flares earlier today – an X1.7 at 3:01 a.m. CDT and an X2.1 at 10:03 a.m. Together the renewed activity indicates the current solar or sunspot cycle still has some life left despite being the smallest or weakest since February 1906.
Sunspots, flares and other solar activity recur in cycles lasting about 11 years. At cycle bottom, weeks can go by without a single spot marring the sun’s perfect white disk. During peak activity, sunspots and the flares they spawn are routine with some spots large enough to easily see with the naked eye and safe solar filter.
Some cycles like those that maxed in 1989 and 2001 are double-peaked with a lull between periods of high activity. Cycle 24 appears to be shaping up to be the same with an early peak in 2011, a dip in 2012 and early 2013 and the present upswing. We’ll have to watch to be sure.
Moments ago I looked at the sun in a small telescope and can tell you firsthand it’s a spotty beast. The two large groups – active regions 1875 and 1877 – dominate the disk, but up-and-comer 1882 looks impressive with a pair of large, dark spots leading the parade.
For quick solar views I use a 3-inch refracting telescope outfitted with a glass filter that removes of the incoming sunlight to create a safe and comfortable image. If you have a telescope I highly recommend purchasing a filter, so you can enjoy the daily march and evolution of sunspot groups as they cross from east to west across the sun’s face. Large, active groups can often be followed from the time they enter the disk until the sun’s rotation carries them to the other side, a period of about two weeks. Changes in sunspot number and appearance greet the eye every single day. Check out Orion Telescopes, Thousand Oaks Optical or Kendrick Astro Instruments for more information about purchasing a safe filter.
With the sun, you never quite know what to expect. After all, it’s a star, full of fire and fury just like the tiny, twinkling ones dotting the night sky. And while they appear deceptively peaceful, the sun teaches us that stars are anything but.
While X-class flares are major events and can cause potential damage to satellite electronics and poorly protected power grids on the ground, Earth’s atmosphere acts as a protective blanket from both particle bombardment and the damaging ultraviolet and X-ray radiation they fling out way. Thank your lucky stars the next time you see the aurora pulsing overhead – a very real probability in light of the latest uptick – knowing that the air molecules are doing their job of shielding life from the sun’s stormy moods.
The atmosphere isn’t the perfect defense especially if you spend a lot of time flying. Radiation from strong solar storms as well as cosmic rays and their by-products can reach down to altitudes flown by commercial airlines, increasing a passenger’s risk of developing cancer over time. Dose rates in over-the-pole flights to destinations like the Far East are 3-5 times higher than flights closer to the equator. Earth’s magnetic field guides cosmic rays and solar particles straight to the polar regions.
Having just returned from 9 hours at 35,000 feet I do feel a little crispy, but the jet lag’s much worse.