Predicting sunspots

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Astronuc
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Sunspot-Spotting Method May Improve Solar Storm Warnings
http://www.space.com/12668-sunspot-prediction-solar-storms-warning.html

Early-warning system for sunspots
http://physicsworld.com/cws/article/news/46914

PhysicsWorld said:
Emerging storms
Now, Stathis Llonidis and colleagues at Stanford University have taken this theory as the basis for a technique to locate the emergence of sunspots within the interior of the Sun. Llonidis' team uses a specific helioseismology technique – called time–distance helioseismology – to analyse the time taken for these acoustic waves to propagate through the solar interior.

The technique involves selecting a pair of points on the solar surface separated by a specific distance between 100,000–200,000 km. Some of the acoustic waves excited near the location of one of these points will propagate 60,000 km into the Sun before returning to the surface near the location of the corresponding point. It usually takes about one hour for the acoustic waves to make this journey. However, if the waves pass through an emerging sunspot, then they speed up and the journey time is reduced slightly – for a large sunspot region this effect is about 12–16 s.
AIAA said:
Stathis Ilonidis used SOHO and Solar Dynamics Observatory satellite data to make the advanced predictions.
Sun storms 'could be more disruptive within decades'
http://www.bbc.co.uk/news/science-environment-14580995

BBC said:
The work, published in Geophysical Research Letters, predicts that once the Sun shifts towards an era of lower solar activity, more hazardous radiation will reach Earth.

The team says the Sun is currently at a grand solar maximum.

This phase began in the 1920s - and has lasted throughout the space age.

Mike Lockwood, professor of space environment physics at Reading, said: "All the evidence suggests that the Sun will shortly exit from a grand solar maximum that has persisted since before the start of the space age.

"In a grand solar maximum, the peaks of the 11-year sunspot cycle are larger and the average number of solar flares and associated events such as coronal mass ejections are greater.
Other threads (some in Astronomy and others in Astrophysics) about sunspots or related solar physics:

Solar Cycle & Explanation for Recent Changes? (Mar-May 2007)
https://www.physicsforums.com/showthread.php?t=162450

Disappearing Sunspots, Minus 50 Gauss/yr
https://www.physicsforums.com/showthread.php?t=413588

Solar Cycle 24
https://www.physicsforums.com/showthread.php?t=363692

Sunspots
https://www.physicsforums.com/showthread.php?t=392837

Density of solar flares?
https://www.physicsforums.com/showthread.php?t=187795
 
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Answers and Replies

  • #2
Drakkith
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Thanks Astro!
 
  • #3
Dotini
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Important new science and some nifty video from the venerable SOHO, newer SDO mission, and those wonderful folks at NASA. Link to new Science paper.

http://science.nasa.gov/science-news/science-at-nasa/2011/25aug_sunspotbreakthrough/
Astronomers have been studying sunspots for more than 400 years, and they have pieced together their basic characteristics: Sunspots are planet-sized islands of magnetism that float in solar plasma. Although the details are still debated, researchers generally agree that sunspots are born deep inside the sun via the action of the sun’s inner magnetic dynamo. From there they bob to the top, carried upward by magnetic buoyancy; a sunspot emerging at the stellar surface is a bit like a submarine emerging from the ocean depths.

In the August 19th issue of Science, Ilonidis and co-workers Junwei Zhao and Alexander Kosovichev announced that they can see some sunspots while they are still submerged.

Their analysis technique is called "time-distance helioseismology2

http://www.sciencemag.org/content/333/6045/993.abstract

Respectfully submitted,
Steve
 
  • #4
Sunspot predictions do not have a good accuracy record. Specifically, predictions from cycle 23 and earlier cycles to our current cycle 24 have been all over the place. However, space weather predictions of coronal mass ejections seem highly correlated with variations of radioactive decay rates observed as much as several days in advance.

Radio active decay rates are supposedly immune to outside influences. Recent observations show this is not the case. The decay rate is experimentally seen to vary prior to coronal mass ejections, as well as seasonal variations during the earth's elliptical orbit.
 
  • #5
Dotini
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...space weather predictions of coronal mass ejections seem highly correlated with variations of radioactive decay rates observed as much as several days in advance.

Radio active decay rates are supposedly immune to outside influences. Recent observations show this is not the case. The decay rate is experimentally seen to vary prior to coronal mass ejections, as well as seasonal variations during the earth's elliptical orbit.
Thank you for posting this, but it should best be accompanied by an acceptable reference per form rules. Not long ago, I posted this same information elsewhere in the forum, citing a PF forum acceptable reference to back it up. Nobody who responded could get over the "giggle factor."

Respectfully,
Steve
 
  • #6
Dotini
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I've recently read Stuart Clark's excellent work, "The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began".

Apart from blood red aurorae down to the Carribbean, and telegraph paper being set alight by the wires, the Carrington Event didn't cause too much stir. Even so, another such flare/CME would be a stern test of our modern power grid to withstand without advance warning, I agree. I have searched, so far in vain, to discover if power grid transformers are still being manufactured in the USA. Do you know?

Respectfully yours,
Steve
 

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