Sun more active than for a millennium: New Scientist

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Ivan Seeking
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The dark patches on the surface of the Sun that we call sunspots are a symptom of fierce magnetic activity inside. Ilya Usoskin, a geophysicist who worked with colleagues from the University of Oulu in Finland and the Max Planck Institute for Aeronomy in Katlenburg-Lindau, Germany, has found that there have been more sunspots since the 1940s than for the past 1150 years.

http://www.newscientist.com/news/news.jsp?id=ns99994321
 
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Originally posted by Ivan Seeking
http://www.newscientist.com/news/news.jsp?id=ns99994321

Interesting, when you gave the original link sometime weeks ago, I happen to be working on a short-time course in Astronomy, which was dealing with sunspots. The course book stated that Sunspots are "cooler' area's of the surface of the Sun.

I had automatically attributed the new activity with sunspots over the 11yr cycle, but the new spots seem to be out of phase. If the Sun actually has more cooler parts upon its surface, then as with normal 'phase' dynamics, it could be approaching another mode of periodic cooling, which acts over longterm times.

The 'flip' from a steady epoch where the surface of the sun remains within a nearly constant in surface temperature terms, would have a short period of where the Sun cools down rapidly with the appearence of Sunspots as a significant sign, then the Sun would settle down with a overall surface temperature that is 'cooler' which would be over a longer period.

The 11yr sunspot cycle is the frequency, but the cause of this cycle itself has another 'frequency', which may be over a greater number of years, the oscillations become apparent when at a cetain moment the both frequencies (11yr sunspot 'short-term' cycle, and the longer-term surface temperature cycle) fall along the same phase sequence.

The University book I have states the surface sunspots as a 'cooler area's', we tend to forget that that Star in our everday sky has been around for quite some time longer than we as humans, and there may be processes that we take as standard, based on our very limited timescale we have studied it?
 
The aurora borealis is seen over the town of Hyvinkaa in southern Finland

Great pic:

http://news.yahoo.com/news?tmpl=story2&u=/031031/photos_sc/mdf396239&e=3&ncid=1756
 
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Sun Shoots 10th Major Flare Tuesday, Possibly Strongest Yet

The 10th major flare in two weeks leapt from the Sun Tuesday, adding one more colossal eruption to a list that has already made history. This one could be the strongest yet.

Scientists are still evaluating the power of the latest outburst, which occurred at about 2:40 p.m. ET. It has tentatively been ranked at least an X17 on a scale in which X denotes severe and the number rates just how severe. [Animations below]

http://space.com/scienceastronomy/solar_flare_031104.html
 
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Originally posted by Ivan Seeking
http://www.space.com/scienceastronomy/xtreme_flare_031105.html

Great images and there will be more. The Suns rotation over 25 days will have ensured that when the sunspots next face Earth, we can expect another dose?

I would be interested if the number of sunspots now active can merge? and even though the sunspots will be on opposite side of the Sun, what sort of effect on Mercury or Venus.

There is a small chance that Voyager penetrating the Heliosphere can inflict a little 'chaotic reverberation' within our Solar System, and have a consequence on the Sun itself, this may be relative to what is happenning on the surface of the Sun, due to shift in Tidal Force imbalance, I speculate this on first examination of the limited data I have access to, but it does seem that the Pressure of our Local Bubble can have a 'reverbarating effect'.
 


Originally posted by ranyart
Great images and there will be more. The Suns rotation over 25 days will have ensured that when the sunspots next face Earth, we can expect another dose?

I would be interested if the number of sunspots now active can merge? and even though the sunspots will be on opposite side of the Sun, what sort of effect on Mercury or Venus.

There is a small chance that Voyager penetrating the Heliosphere can inflict a little 'chaotic reverberation' within our Solar System, and have a consequence on the Sun itself, this may be relative to what is happenning on the surface of the Sun, due to shift in Tidal Force imbalance, I speculate this on first examination of the limited data I have access to, but it does seem that the Pressure of our Local Bubble can have a 'reverbarating effect'.

This has been quite a story...I am waiting to see the flash in my window when the X200 hits.

Are coronal mass ejections included when calculating the life of a star i.e. could the total loss of mass be significant?
 
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Originally posted by Ivan Seeking
This has been quite a story...I am waiting to see the flash in my window when the X200 hits.

Are coronal mass ejections included when calculating the life of a star i.e. could the total loss of mass be significant?

Ihave already dug out my "eclipse-shades" !
 


Originally posted by Ivan Seeking
This has been quite a story...I am waiting to see the flash in my window when the X200 hits.

Are coronal mass ejections included when calculating the life of a star i.e. could the total loss of mass be significant?

Well from the normal "dieting!" programs usually associated with Humans, the more 'MASS' loss usually means that Humans become more active! A 600lb Human can't deliver the morning paper as fast as a 300lb deliveryboy?

The amounts(CME), would have to be quite huge, ALTHOUGH? technically I think there are internal considerations that relate to Photons emerging from deep within the Core, the usual timescales are I believe dependent upon the density of the Star?..therfore if a Star 'sheds' enough mass, then its photons should arrive at its surface a lot quicker?
 
I've been listening to George Noory Radio show, and he had an astronomer on for an interview about the very unusual sun activity. He claimed that the CMEs weren't from the sun itself but from a barage of cometary impacts. The comets are making a direct hit from the south. I have been watching the sun with my telescope lately. The spots are on the south of the suns equator.
What do think?
 


Originally posted by Ivan Seeking
This has been quite a story...I am waiting to see the flash in my window when the X200 hits.

Are coronal mass ejections included when calculating the life of a star i.e. could the total loss of mass be significant?
The CME's are considered in calculating the life of a star, but on the Main Sequence, like our Sun, even the large CME's are a very, very small % of the total solar mass. Only in "late stages" of evolution do CME's eject enough mass to be significant. In a star like ours, this would be after the "Helium Flash", expected in ~4 Billion years.

The "cooler" sunspot areas are still hot at ~9,000 F., while the normal photosphere is ~11,000 F. Cool is just relative. As for ranyart's last posts, a star the size of ours will always have a radiative core and convective outer layers; the density is not high enough to inhibit radiation from the core. In massive stars, the cores are convective and the outer layers are radiative; the core density is too high to even allow radiation a "direct route" to outer layers. For a good bit of general info on our Sun, and CME's, see:

http://www.solcomhouse.com/solar.html

Labguy
 
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