Solar cycle primer

Oct 28, 2011 by Karen C. Fox
Eleven years in the life of the Sun, spanning most of solar cycle 23, as it progressed from solar minimum (upper left) to maximum conditions and back to minimum (upper right) again, seen as a collage of ten full-disk images of the lower corona. Credit: NASA

(PhysOrg.com) -- Telescopes spotted the first blemish on the sun in 1611. While the sun had long been thought—at least in the Western world—to be an unchanging, "perfect" orb, sky-watchers observed black sunspots on the sun's surface that circled around as with the sun's rotation.

That first crack in the theory of the sun's immutable nature would soon fracture completely as the number of sunspots were shown to increase and decrease over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can vary. It has been as short as eight years and as long as fourteen, but the number of sunspots always increases over time, and then returns to low again.

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Credit: NASA/Goddard Space Flight Center/Scientific Visualization Studio

More sunspots mean increased solar activity, when great blooms of radiation known as solar flares or bursts of solar material known as coronal mass ejections (CMEs) shoot off the sun's surface. The highest number of spots in any given cycle is designated "solar maximum," while the lowest number is designated "solar minimum." Each cycle varies dramatically in intensity with some solar maxima being so low as to be almost indistinguishable from the preceding minimum.

One such set of cycles famously occurred from 1645 to 1715 and is known as the Maunder Minimum. Those who watched the sun could count enough change in sunspot number that they could still track cycles, but the overall sunspot number dropped drastically. One thirty-year period showed only 30 sunspots, one thousandth of what is typically seen.

The timing of the Maunder Minimum corresponded to what's called the Little Ice Age in Europe—a time of colder weather, heavier snowfall and the freezing of unusually large bodies of water such as the Thames and even the Baltic Sea. The Little Ice Age lasted longer than the Maunder Minimum, and there are other potential causes. Nevertheless it is believed by many scientists that the prolonged solar minima and its corresponding decrease in solar energy cooled Earth. Mapping out the details of how much the change in solar energy could have produced such an effect remains an unresolved area of research.

Early records of sunspots indicate that the Sun went through a period of inactivity in the late 17th century. Very few sunspots were seen on the Sun from about 1645 to 1715. Credit: NASA/MSFC

It was not until the first half of the 20th century that scientists began to understand what causes the sunspot cycle. Researchers determined that the sunspots were a magnetic phenomenon and that, indeed, the entire sun was magnetized with a north and a south magnetic pole just like a bar magnet. The comparison to a simple bar magnet ends there, however, as the sun's interior is constantly on the move.

By tracking sound waves that course through the center of the sun, an area of research known as helioseismology, scientists can gain an understanding of what's deep inside the sun. They have found that the magnetic material inside the sun is constantly stretching, twisting, and crossing as it bubbles up to the surface. The exact pattern of movements is not conclusively mapped out, but over time they eventually lead to the poles reversing completely.

The sunspot cycle happens because of this pole flip — north becomes south and south becomes north—approximately every 11 years. Some 11 years later, the poles reverse again back to where they started, making the full solar cycle actually a 22-year phenomenon. The sun behaves similarly over the course of each 11-year cycle no matter which pole is on top, however, so this shorter cycle tends to receive more attention.

The sun is currently ramping up once again to solar maximum, so flares and CMEs are more common than they were a few years ago. This cycle may peak in late 2013, or early 2014, and should reach a minimum around 2020—although predictions about the sun's cycle are still quite uncertain. This has been the slowest of the space age, which is the time frame during which we have the most detailed observations.

The slower-than-expected progress of this cycle has led some researchers to speculate that the next cycle might be even smaller, with few sunspots even at solar maximum. It is still far too early to know, but even if this is the case, it has happened before and isn't a cause for concern. Four hundred years of sunspot observations have shown that the cycle will always return.

Explore further: Amazing raw Cassini images from this week

More information: For more about sunspots, visit: solarscience.msfc.nasa.gov/SunspotCycle.shtml

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User comments : 22

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ryggesogn2
2.5 / 5 (13) Oct 28, 2011
But solar cycles have no effect upon 'global climate change'.
nejc2008
4 / 5 (4) Oct 28, 2011
Well, here we have one who KNOWS! Congratulations.
omatumr
1.4 / 5 (11) Oct 28, 2011
Thank you for this reminder on the natural variability of Earth's heat source - the Sun.

Several studies reported that the cycles are induced by solar wobble from gravitational interactions between orbiting planets and the solar core (1-4).

That is why we need to know if the solar core is an iron-encased pulsar (5).

1. P. D. Jose, Suns motion and sunspots, Astron. J., 1965, 70, 193-200

2. R. W. Fairbridge and J. H. Shirley, Prolonged minima and the 179-yr cycle of the solar
inertial motion, Solar Physics, 1987, 110, 191-220

3. Superfluidity in the solar interior: Implications for solar eruptions and climate, Journal of Fusion Energy, 2002, 21, 193-198 http://arxiv.org/.../0501441

4. "Earth's Heat Source- The Sun," E&E, 2009, 20, 131-144 http://arxiv.org/pdf/0905.0704

5. "Neutron Repulsion", The APEIRON Journal, in press (2011)

http://arxiv.org/...2.1499v1

With kind regards,
Oliver K. Manuel
http://myprofile....anuelo09

Callippo
1.7 / 5 (7) Oct 28, 2011
But solar cycles have no effect upon 'global climate change'.

The eleven years cycles not, but the minimum of solar activity do - the so called Maunder minimum as apparent connection to the medieval era of cold winters.

http://en.wikiped...bers.png

But the people are surprisingly ignorant to explanations of both climatic cycles, both solar cycles. For example, the eleven years standing period of Solar activity has a connection to the motion of Jupiter planet - but from some reason no one of mainstream physics analyzed this connection deeper. Although this connection is quite apparent, from some reason the publications about it never got into peer-reviewed journals and the people who are dealing with this periodicity are generaly considered crackpots.

This illustrates clearly, the contemporary implementation of science still suffers with deep flaws.
omatumr
1.3 / 5 (13) Oct 28, 2011
the so called Maunder minimum as apparent connection to the medieval era of cold winters.

http://en.wikiped...bers.png

the eleven years standing period of Solar activity has a connection to the motion of Jupiter planet - but from some reason no one of mainstream physics analyzed this connection deeper.


Government science was misdirected after 1971 to support the Bilderberg model of the Sun as a stable heat source "in equilibrium".

Conflicting observations, even from very talented astrophysicists like Dr. Carl A. Rouse [1, 2], were ignored.

[1] Dr. Carl A. Rouse (PhD, Cal Tech)
www.omatumr.com/P...desc.htm

[2] "Evidence for a small, high-Z, iron-like solar core," Astronomy & Astrophysics 149, 65-72 (1985):

http://articles.a...49...65R

omatumr
1.3 / 5 (13) Oct 28, 2011
Carl A. Rouse earned his PhD in particle physics at Cal Tech in 1956.

"A researcher at heart who avoided the classroom, while working in private industry he branched out into astrophysics and in his writings and lectures challenged mistaken hypotheses concerning intensely hot gases that constitute the sun and stars."

www.math.buffalo....rla.html
Callippo
2 / 5 (12) Oct 28, 2011
omatumr: The posts of yours aren't related to sun cycles in any logical way presented. You're just abusing the visitors of this discussion instead of your children, but from the same reason: you're living in the world of your fantazies.
omatumr
1.4 / 5 (9) Oct 28, 2011
I failed to explain that solar cycles occur BECAUSE changes in SIM (solar inertial motion) cause the Sun's dense energetic core to be jerked around - like a yo-yo on a string - inside the glowing ball of waste products (photosphere = 91% H 9% He) that obscures the solar core.
omatumr
1.4 / 5 (10) Oct 28, 2011
I failed to mention that solar cycles occur BECAUSE changes in SIM (solar inertial motion) cause the Sun's dense energetic solar core to be jerked around - like a yo-yo on a string - inside the glowing ball of waste products (photosphere = 91% H 9% He) that obscures the solar core.
Callippo
2 / 5 (8) Oct 28, 2011
I failed to explain that solar cycles occur BECAUSE changes in SIM (solar inertial motion) cause the Sun's dense energetic core to be jerked around - like a yo-yo on a string - inside the glowing ball of waste products

This effect has nothing to do with Sun composition, as it can occur even in classical models of solar fusion, which are considering the existence of dense solar core too. So that all your links above are irelevant to subject.
omatumr
1.4 / 5 (9) Oct 28, 2011
Do you really think that the position of the compact, dense solar core remains fixed in the exact center of the Sun during changes in solar inertial motion?

Are you aware of an instrument called a "shaker" ? It is used to mix paint.
Callippo
2.2 / 5 (10) Oct 28, 2011
Of course, the dense solar core exists in standard solar model too. We don't need any omaturm to realize it.

http://en.wikiped...ar_Model

As I explained here many times, the motion of solar core is affected with position of the center of mass of solar system, which is driven with motion of Jupiter and other planets. It affects the convection of solar plasma with Coriollis effect.

Again, it has anything to do with your silly links and it could be deduced from any solar model.
omatumr
1.3 / 5 (12) Oct 28, 2011
Of course the dense solar core exists in standard solar model too.


Shaking [changes in SIM - solar inertial motion] causes mixing of material with different densities

The Sun's pulsar core is much more dense than ordinary atomic matter.

That is why the pulsar-centered Sun explains better than the standard solar model:

a) Solar cycles and many other observations that lock-step consensus scientists ignored for the past four decades (b,c,d,e,f,):

b) "Super-fluidity in the solar interior: Implications for solar eruptions and climate"
J Fusion Energy 21, 193-198 (2002)

http://arxiv.org/.../0501441

c) "Composition of the solar interior" ESA SP-517, 345-348 (2003)

http://arxiv.org/...410717v1

d) "Earth's Heat Source - The Sun", E & E 20, 131-144 (2009)

http://arxiv.org/pdf/0905.0704

e) "Neutron repulsion" (in press)

http://arxiv.org/...2.1499v1

f) Climategate history (1971-2011)
http://dl.dropbox...oots.pdf
hyongx
4.2 / 5 (5) Oct 28, 2011
I like this article, because I learned something new, that I didn't know, about sun-spot cycles. Theoretical models speculate, while experimental observations provide information to support or discredit theoretical models. Science proceeds as per usual.
Mr. Oliver, your posts are, as per usual, entertaining and mostly irrelevant. :)
jsdarkdestruction
2.6 / 5 (5) Oct 29, 2011
i love it when those 2 go at it. Callipo, you are actually the most sane person in the argument. After reading through your past 20 posts i was getting kind of sick of it but these made me smile. i think you should do that with all of olivers post. it would make the world a better place for us all.
Callippo
3 / 5 (8) Oct 29, 2011
i think you should do that with all of olivers post
It has no meaning to dispute with him. He will just repeat his usual list of links prepared for clipboard paste.
jsdarkdestruction
3.4 / 5 (5) Oct 29, 2011
but it makes you look so much better than your normal posting does....look at that, you just got a bunch of five scores(by me), whens the last time that happened?(answer=last time you called olivers nonsense out.)
Callippo
1 / 5 (4) Oct 29, 2011
This is not a social club and I'm not here for collection of credits. You should use a PM feature for such kind of messages. If you don't want to see the very same links all the time, just report the abuse. Or you're just helping the spammers to attract attention to their person.
barakn
5 / 5 (5) Oct 29, 2011
...changes in SIM (solar inertial motion) cause the Sun's dense energetic core to be jerked around - like a yo-yo on a string ....
The Sun does indeed orbit around the barycenter of the solar system, but it does so in free-fall, simply following a straight line in curved spacetime. This is similar to an stronaut orbiting the Earth, who's linear inertial motion has been constrained into an ellipse by gravity but who feels weightless. If anything is going to jerk the Sun's core relative to outer layers it is the gravity gradient, or tidal forces, and analysis of the primary motion around the barycenter will tell you little about the tidal forces.
andre_5200
1 / 5 (4) Oct 29, 2011
Have we forgotten about frequencies, and or, metaphysics, they too doctrine our minute planes?
Egnite
not rated yet Oct 31, 2011
..isn't a cause for concern. Four hundred years of sunspot observations have shown that the cycle will always return.


Yeah, monitoring a 4.6 bilion year old star for 400 years will give you a great indication of any patterns that could exist. Arrogant much?
omatumr
1 / 5 (4) Oct 31, 2011
The Sun does indeed orbit around the barycenter of the solar system, but it does so in free-fall, simply following a straight line in curved space-time.


The link of solar inertial motion with Earth's climate, solar cycles and sunspots was known even before we realized the solar core is a pulsar, about 1,000,000,000,000,000 more dense than ordinary atomic matter.

See the review paper by Richard Mackey, "Rhodes Fairbridge and the idea that the solar system regulates the Earths climate"

www.griffith.edu....S176.pdf

Two of many earlier papers:

1. J. D. Jose, Suns motion and sunspots, Astron. J. 70, 193-200 (1965)

2. R. W. Fairbridge and J. H. Shirley, Prolonged minima and the 179-yr cycle of the solar
inertial motion, Solar Physics 110, 191-220 (1987)