Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Karen W. on 17/12/2006 16:37:58
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Can someone tell me exactly what a solar flare is? I have some basic ideas that I believe are not accurate, but I have been hearing about how we are experiencing many right now! I am in Northern California, Are these visible to the naked eye? Can one see them with a telescope and are they more prevalent now for some reason? I could go on as I know very little. Please feel free to use your simplest explanation as that would be better for my delicate brain...LOL Easily understood would be nice! Thanks!
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As far as I undersand them flares are surface phenomena on the Sun.
They're not the big looping arches of plasma that you see in the really impressive photos. They are solar prominences.
They look like very fast and intense cracks on the surface that are caused by the breaking of magnetic force lines which releases huge amounts of energy.
All this energy released causes lots of plasma and gas to be ejected from the Sun and travel out into space.
The big blobs of gas ejected are coronal mass ejections.
You can see them with a telescope but not a normal one.
Well you could use a normal one but you're not going to get the best view as the amount of light coming into your eye would burn a hole all the way to the back of your skull and it'd be off to the hospital with you.
The best way to view the Sun is to use a telescope fitted with a Hydrogen Alpha filter which filters out all radiation apart from that emitted by charged hydrogen.
Using one of these H-Alpha filters you get the red view of the sun where you can see all the details.
You can see the corona, sunspots and flares happening on the surface. With very high magnifications you can see the granular structure of the surface created by convection cells.
The Sun's activity is cyclical. As I remember we're in a period of low activity.
Someone pick me up here if I'm wrong.
So the amount of activity on the Sun varies in a 22 year cycle. High through almost none to low and then back through almost none to high activity again.
That's why it varies.
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Thats very interesting and your explanation was superb. I am able to understand your explanation. I had just been talking with several people who were teling me about these solar flares. I knew very little, and none ofthat which you explained. May I ask, another question? Do Sunspots occur due to solar flares? If not what causes them. As I know in the past as far as my satelite dish was concerned that at times we would have sun spots which would cause problems in reception and recording of incoming feeds of which we were veiwing via my satelite dish!
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Sunspots are associated but they are not caused by flares.
Sunspots tend to last for quite a long time and are areas of high magnetic field intensity which cools down the hot gas so that the spot looks black when shown next to the extremely bright surface.
They're actually not black at all. Their temperature is [memory failure] about 4000 kelvin [/memory failure] compared to the rest of the surface at about 6000 kelvin.
So they look dark.
No sure what causes sunspots. Local magnetic anomalies probably. I'd have to go back to my notes and look it up.
Satellite sunspots. [;D]
It's actually not sunspots that cause the problems with TV reception.
It is caused by coronal mass ejections.
All that super hot plasma ejected off the Sun sometimes comes heading in the right direction so that it hits the Earth.
Well it hits the Earth's magnetic field.
The charged particles get shoved by our magnetic field towards the North and South poles where their effects can be seen as the aurora.
All these particles induce massive electrical currents which also emit more magnetic energy and electromagnetic energy.
This energy in received by your satellite receiver and sometimes overwhelms the broadcast signal so you get noise and dropouts and other disturbances etc...
Generally when the Sun is more active there are more sunspots and more coronal mass ejections so more interference.
Sunspots have been known about for hundreds of years but the mass ejection part is a recent discovery.
That's why people tend to associate sunspots with interference.
"You're breaking up ! I've got sunspots !"
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As a firm believer in empirical study I created some ball lighting and chucked in some grains of fire work powder. It flared !
Conclusion. Someone keeps chucking fireworks into the Sun.
Glad I could help .
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YAYYYYYY< Me love fireworks...DO IT AGAIN!!!!LOL
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in the 1947 when we only had one rather low power TV station broadcasting on the low end of the VHF band it was a time of high Solar activity and flares occasionally caused enough radio noise to wipe out the TV signal 50Km from the station.
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Thats amazing. In the late 80's we experienced enough of them to cause huge chunks of videos we were recording from a satelite to be blank. For Instance My copy of Gone with the wind had an episode after the town blaze where the solar flare just knoced it out for a good size chunk of the recording! It was so weird!