Saturday, February 19, 2011

How's the (Space) Weather?

 This post will also be found in Tehachapi's The Loop Newspaper.

After a long period where the Sun was fairly inactive, the number of sunspots is up to 63. With one, called 1158 of huge size. (Check out to keep up-to-date on what's going on out in space.) This one sunspot is about 62,000 miles across. And the earth is about 8,000 miles across at the Equator. So we could line up about 8 Earths across this sunspot.

And this sunspot is along the solar latitudes where ejections could come towards Earth. But for the most part these storms on the sun don't have a lot of affect on us here on Earth. The magnetic field of the Earth pulls the particles from any such ejection towards the Earth's poles. And the interactions of the solar particles with the magnetic field generates the auroras (Northern or Southern Lights). So we can get more spectacular displays when the sun gets more active.

And for the most part that's all that happens. Though GPS and satellite communications can be affected. However the February 2011 Sky and Telescope magazine article “The Perfect Solar Superstorm” has some tales of some problems that have been caused here on Earth by some very large Solar storms.
In March of 1989, Quebec had a 12 hour power outage caused by solar ejection. The magnetic fields induce currents in the wires forming our electrical power grids. These “extra” currents can cause the transformers and other components to fail which can shut down power to huge areas.

The largest recorded affect from a solar ejection was back in 1859. The aurora was visible down to the Caribbean. Much of the world was crossed by telegraph wires and the currents set up in the telegraph wires shocked many telegraph operators. Some of the telegraph poles emitted sparks and telegraph paper caught fire. It was even reported that there was enough power in the lines for the telegraph operators to continue to send signals even after they had disconnected the power from the system.

So, are we at greater risk for a disruption today? The risk is greater with our vastly increased usage of communication technologies (cell phones and the Internet, etc.). But we also have better resources for detecting the solar ejections which gives us minutes to hours of warning. Which allows the operators of our communication and power grids to prepare for the extra currents which should reduce the severity of the problems cause. 

We are benefiting directly from investments in satellites that have been sent up to observe the Sun such as the SOHO satellite. (SOHO stands for Solar and Heliospheric Observatory. And heliospheric is just a big word for the Sun's atmosphere.) So we're learning more about the Sun and can see what's happening there before it has a chance to affect us.

Right now we're having the Sun ramp back up after a long minimum in its (approximately) 11 year sunspot cycle. The maximum is being predicted for summer of 2013. And for now the forecast is for the weather on the Sun to be mild. Though of course, like all weather predictions, it is subject to change.


  1. Very cool! I am enjoying the Sky and Telescope Magazine. Haven't been viewing much of the stars lately since I am a wimp in the cold temps but the ring around the moon last week was beautiful.

  2. Wasn't it? Maybe in a couple weeks out in the desert there will be a chance to look up too.