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The Sunspot Cycle Explained
An anonymous reader writes "After the recent spate of auroras visible as far south as Florida and Greece, and radio amateurs having lots of fun bouncing their signals off the auroral curtain, maybe some explanation was needed. It has been known for a while that the peak of solar activity trail trails the sunspot cycle peak by a couple of years, but this BBC article appears to explain why. As you may expect most of the data came from the SOHO satellite and the theory has been put together by some scientists using what appears to be data mining."
As easy as one, two, three.
Yes, it did actually make it that far. I have a friend who saw them easily in IN, and FL is hardly much further south.
You can monitor current auroral activity here.
You probably failed to see the lights due to the intense light pollution on the eastern seaboard, which is also the reason why there are no major observatories in the eastern states.
He who laughs last is stuck in a time dilation bubble.
This very radiant natural lightshow is mostly enjoyed by people living far north where there is no streetlights obscuring the show.
//Pingo
However in recent weeks there has been very strong aurora far south and if you would like to know when it's time for a great show, check this NASA webpage http://sec.noaa.gov/rt_plots/satenv.html
The last plot with the 'Estimated Kp' is what to look for. When the number is around 9, then there is great Aurora to be seen if the sky is clear and no streetlights around.
If you live far north, then you might see Aurora with lesser values of this Kp index. Red bars in the plot is needed however.
--- Linux or FreeBSD, it's like blondes or brunettes. I like both. ---
Those who live and work in the high latitudes - such as in those few sources the US has where there is oil pay a lot of attention to sunspots. Communication disruptions are the biggest problem. Much more rare are power failures - but they have been known to bring down entire power grids. In 1986, British Columbia had a huge power failure. Not all the evidence is in about the recent East coast power outage - They still haven't determined what caused the lines to overheat in the first place - The Ohio company appears to have made mistakes - but they may also just have been trying to keep up with too much demand on the grid all day. Solar flares affect the grid in unexpected ways. That's one of the many reasons they're being watched so closely.
I've probably seen the aurora 300-400 times. It is one of the beautiful things to my eye in nature. If it's out, in my experience - it can change in 5 minutes time from close to nothing to wild. Photos don't do it justice - but this site has some movies too, that give just a slight feel of it.
The BBC article is very simplified - A fairly new technique - called "helioseismic holography" allows astronomers to actually 'look through' the sun to image the magnetic fields of very large sunspots like the present pair (they occur in pairs - corresponding to a north and south magetic pole).
This present sunspot pair is the largest we've ever measured.
The particles themselves don't really emit the light - "the electrons that cause auroras do not come directly from the Sun"
Sunspots can be seen under certain lighting conditions when the sun is rising or setting even with the naked eye.
Chinese astonomers recorded them long before they were one of the first things that we're recorded by the inventors and early users of the telescope.
Sunspots - a reduced number of them - have been correlated with cooler weather trends.
There was about a 70 year period of fairly recent time - 1645 -1715 that apparently saw no auroras - even at high latitudes - kids thought they were mythical stories by the time they appeared.
The solar flare a few weeks ago was the strongest we've ever measured, and we can expect to see more as that same pair of sunspots rotates around to face Earth.
The solar eclipse will be tomorrow - there will be some great photos that will come out in the next few days.
Well its a SOLAR satellite.
Wanted : A Signature.
were visible with the naked eye a few weeks back when we had the fires here in southern california, the smoke was so thick, you could still see the sun, but not in its right glory, you could see the big sunspots as shown here: http://sohowww.nascom.nasa.gov/sunspots/
it was interesting to say the least..