By Jo Nova

The big sunspot cluster that created the auroras a few weeks ago is very likely just over the horizon on the sun, and it appears to have spat out a doozy of an X2.9 flare to announce its return. While we can’t see the sunspots themselves yet, astronomers estimate that they are the same angry AR3664 set that has been circling across the far side of the sun for the last two weeks.  This hyperactive region launched the X class flares that produced auroras on May 10th that were so powerful they lit up the skies far from the poles in Florida and Queensland.  Some officials at NASA even think it was  “one of the strongest auroras in 500 years”. They argue that some 7 different coronal mass ejections traveling at 3 million miles per hour, piled up together on the way and arrived all at once. In the last 70 years the other two big events were in 1958 and 2003. The Carrington event was so big it was seen in the Caribbean.

But the solar storm a few weeks ago was big enough that it reached down and twiddled with compasses on the sea floor as far as 2.7 kilometers (1.7 miles) underwater. So we are left with the paradox that solar weather controls half the groundwater refill in China, shows up in patterns of lightning in Japan, and somehow correlates with jellyfish plagues on Earth, but can’t possibly cause climate change. Apparently, your air conditioner can contribute to a heatwave but the vast electro-magnetic dynamo 333,000 times heavier than Earth can not. We know this because a foreign committee in Geneva says so, and they have skill-less models to prove it.

The global climate models agree that the effect of the solar-magnetic-wind and electric-field is exactly 0.0 degrees (per doubling of their NSF grants).

Some very active sunspots may last for months and each full rotation of the sun takes 27 days, so we may get more bites at this cherry. Or, if the sun is particularly grumpy, it may get more bites at us.

As the sun rotates we’ll see more of what is probably AR3664, though when it rolls over the horizon it will promptly get a new number-name. It’s difficult to track exactly what happens to every sunspot cluster as they travel across the far side of the sun, so all sunspots shifting into view are automatically given a new number. Though according to Daisy Dobrijevic at Space.com “scientists can track the sunspot’s progress across the sun’s far side by observing how it affects the sun’s vibrations or seismic echoes, using helioseismology data.” Sounds tricky. You’d think we’d have a camera on an asteroid on the far side recording the sun, but we don’t. We spent $100 billion trying to blame a fertilizer for our storms, but a lot less than that trying to understand the sun.

People who want to see an aurora may get lucky in the next two weeks if a flare is ejected in our direction

Look out for notices of a large X Class flares. Depending on how fast the ejections travel, the charged particles usually arrive here about two days later, but may come anytime from 15 hours to 4 or 5 days later. Once the particles hit the satellites at the Lagrange point the instruments give us about 15 to 45 minutes of warning. The Lagrange point is 1.5 million miles away from Earth towards the Sun in an area where gravitational and centripetal forces equal out, and it takes very little fuel for the satellites to maintain their position. It is the closest thing to a parking spot in space where our space-cars won’t roll away if we’re not looking.

Check the Glendale App for information or sign up for email alerts from the Australian Space Weather Forecasting Centre for aurora or from SpaceWeatherLive. Some bright spark set up Aurorasaurus to track aurora related tweets. Apparently they correlate quite well with geomagnetic indices.

For the record: Solar flares are graded B, C, M and X class, with X being the largest and each grade putting out ten times more energy than the grade before. Within each grade there are nine log divisions (Eg. M1, M2 etc.) There is no upper limit on X class flares and the one in 2003 overloaded the instruments (which max out at X17). It was later estimated to be X45. X class flares can trigger planet wide radio blackouts and potentially widespread auroras. The flares in May were

Thanks to Willie Soon.