Interesting doings at the center of our solar system over the past few weeks.
It started about three weeks ago, when my radio and satellite internet reception went squirrelly. This happens from time to time for any number of reasons, mostly having to do with Earth weather rather than Space weather. As anyone with satellite TV or internet could tell you, storm clouds, charged atmosphere (as in the 'usual' summertime afternoon thunderstorms) and plain old rain can wreak havoc on reception. So can CMEs from our neighborhood star.
Or, as Discover blogger Corey Powell puts it:
You’ll notice that part of the sun is missing . . . This part that’s missing, the reason it’s dark, is that whole chunk of the sun basically ripped off, blew out and is coming our way at about 2 million miles an hour.
Where I live, in a cut-off cove in the steep southern Appalachian mountains of WNC, the past three months have been so darned wet that for awhile there I figured we were in serious need of an ark. Given the average rainfall over that time as right about 11 inches a week (sometimes significantly more), my web searching abilities have been sharply curtailed just in time for apple, tomato and chile pepper harvest time. So I've managed to be pretty productive anyway.
Radio reception, on the other hand, is often enhanced in unstable weather. So long as the transmitter atop Mount Mitchell doesn't get struck by lighting (it happens). I only get one radio station here, which fortunately for me happens to be the best Public Radio station anywhere - WNCW. A constant stream of great local and regional music plus 'the good stuff' on the national scene, weekly Dead Air with Uncle Dave plus Sunday night Reggae fest. Interspersed with hourly NPR news, of course. but for some reason, all I could get was a maddening stream of noisy static. We have no television at all, and while I could play DVDs on the computer, I mostly don't. So it's been strangely quiet.
Until this week, when things have cleared up quite a bit. So in my surfing today I went looking for the best viewing times for the Perseid meteor shower. Which, by the way, is expected to peak Monday-Tuesday in case you're interested. I also found when I was at Space Weather that there's a 60% chance of polar geomagnetic storms Saturday, when a couple of CMEs [Coronal Mass Ejections] are expected to hit, which will bring some of us a nice summer night light show as the aurora heads south. CMEs? More than one? That tickled my curiosity a bit, so I sauntered on over to Science Daily to see what was up.
I learned right there on the main page that The Sun's Magnetic Field Is About to Flip. Which is kind of interesting. Of course, they've been predicting that flip for more than a year (first expected in March of 2012), but you can never really tell about these things. We're at solar max right now Cycle 24 of the sun's 22-year mini-max cycle, during which the magnetic field will do its flip twice. Every 11 years (give or take, since it's been 12 since the last one). Anyway, I'm told the flip is now scheduled to occur within the next three or four months, when the sun's south pole changes its sign. The north pole, we are told, has already changed its polarity...
"What!?!" you say? Yeah. That little tidbit threw me for an ungrounded loop too. Isn't the magnetic field produced by our sun supposed to have both a positive AND a negative pole? I mean, since there's no examples of anything approaching a theoretical beastie commonly known as a "magnetic monopole" that we can find in all our explorations of the universe. Does this mean our star currently has two positive poles? Two negative poles? Or is its magnetic polarity pretty much zero right now? Hmmm...
Over to the right of the page there was a link to another story from July 19th (about the time my reception issues started) announcing a Large Coronal Hole Near the Sun's North Pole. Large hole, eh? NASA doesn't characterize it as merely "large" though. It goes on to call the hole "gigantic." Now, there's a word for you.
Meanwhile, Discover Blog settles for a middling descriptor of "Huge Hole." The existence of this large/gigantic/huge hole in the sun's north means that coronal mass that would usually loop back like the field lines of a magnet to either the south pole of the body or to a lesser surface field's opposite pole instead get sent out into the heliosphere because they've nothing to really connect to. And I'm guessing that this is what's been causing my reception issues of late. Makes more sense to me than that we've got a monopole sun right now, anyway. Which we apparently do until the south pole reverses completely. CMEs I can grok. Monopoles are harder to grasp.
So. Our sun has (or recently had) a "Huge Hole" in its head, sending plasma out into the ether to mess with satellites and radio transmissions and such. Pretty cool, I think. So if you are interested, check out some of the links, and have fun with it!
P.S. I know there are some Kossacks here who can explain to me how, exactly, the sun can have a single working pole at any given time. Thanks in advance!