Solar activity heats up

Apr 15, 2011 Dr. Tony Phillips
NASA's Solar Dynamics Observatory recorded this X1.5-class solar flare on March 9, 2011.

(PhysOrg.com) -- If you've ever stood in front of a hot stove, watching a pot of water and waiting impatiently for it to boil, you know what it feels like to be a solar physicist.

Back in 2008, the solar cycle plunged into the deepest minimum in nearly a century. Sunspots all but vanished, subsided, and the was eerily quiet.

"Ever since, we've been waiting for solar activity to pick up," says Richard Fisher, head of the Heliophysics Division at NASA Headquarters in Washington DC. "It's been three long years."

Quiet spells on the sun are nothing new. They come along every 11 years or so—it's a natural part of the solar cycle. This particular solar minimum, however, was lasting longer than usual, prompting some researchers to wonder if it would ever end.

News flash: The pot is starting to boil. "Finally," says Fisher, "we are beginning to see some action."

As 2011 unfolds, sunspots have returned and they are crackling with activity. On February 15th and again on March 9th, Earth orbiting satellites detected a pair of "X-class" solar flares--the most powerful kind of x-ray flare. The last such eruption occurred back in December 2006.

After years of lying low, sunspot counts are on the rise again.

Another eruption on March 7th hurled a billion-ton cloud of plasma away from the sun at five million mph (2200 km/s). The rapidly expanding cloud wasn't aimed directly at Earth, but it did deliver a glancing blow to our planet's magnetic field. The off-center impact on March 10th was enough to send Northern Lights spilling over the Canadian border into US states such as Wisconsin, Minnesota, and Michigan.

"That was the fastest coronal mass ejection in almost six years," says Angelos Vourlidas of the Naval Research Lab in Washington DC. "It reminds me of a similar series of events back in Nov. 1997 that kicked off Solar Cycle 23, the solar cycle before this one."

"To me," says Vourlidas, "this marks the beginning of Solar Cycle 24."

The slow build-up to this moment is more than just "the watched pot failing to boil," says Ron Turner, a space weather analyst at Analytic Services, Inc. "It really has been historically slow."

There have been 24 numbered solar cycles since researchers started keeping track of them in the mid-18th century. In an article just accepted for publication by the Space Weather Journal, Turner shows that, in all that time, only four cycles have started more slowly than this one. "Three of them were in the Dalton Minimum, a period of depressed solar activity in the early 19th century. The fourth was Cycle #1 itself, around 1755, also a relatively low solar cycle," he says.

In his study, Turner used sunspots as the key metric of . Folding in the recent spate of sunspots does not substantially alter his conclusion: " 24 is a slow starter," he says.

Better late than never.

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User comments : 14

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CapitalismPrevails
1 / 5 (2) Apr 15, 2011
Next year will have solar storm of 1859 all over again.
omatumr
1 / 5 (6) Apr 15, 2011
Thanks, Tony, for this interesting and well-written report on the Sun.

Nothing that astronomers study could be of more importance to the public than quantitative information on Earth's heat source - the Sun.
beelize54
2.6 / 5 (5) Apr 15, 2011
It seems, the global warming period is returning again. It would be unpleasant.
Calenur
4 / 5 (4) Apr 16, 2011
Will you PLEASE do something about these ads? This is getting infuriating.

Tachyon8491
1.7 / 5 (6) Apr 16, 2011
I have reported this arrogant, self-serving commercial sewage several times to Physorg's management - WHEN ARE YOU GOING TO GET RID OF THIS INVASIVE BASTARD!!!
deepsand
3.4 / 5 (17) Apr 17, 2011
Nothing that astronomers study could be of more importance to the public than quantitative information on Earth's heat source - the Sun.

Is this an acknowledgment that the Sun, by virtue of its having been in a protracted MINIMUM, cannot be the cause of global warming?
omatumr
1 / 5 (9) Apr 17, 2011
Nothing that astronomers study could be of more importance to the public than quantitative information on Earth's heat source - the Sun.

Is this an acknowledgment that the Sun, by virtue of its having been in a protracted MINIMUM, cannot be the cause of global warming?


No. The Sun's influence on Earth's climate is explained here:

http://arxiv.org/pdf/0905.0704

The photosphere that we observe:

a.) Is a glowing cloud of waste products (H and He) from the Suns central neutron star:

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

b.) That will eventually expand "to the orbit of Mercury or Venusor even the Earth!

According to NASAs Dr. Sten Odenwald:

www.astronomycafe...958.html

deepsand
3.4 / 5 (15) Apr 17, 2011
Nothing that astronomers study could be of more importance to the public than quantitative information on Earth's heat source - the Sun.

Is this an acknowledgment that the Sun, by virtue of its having been in a protracted MINIMUM, cannot be the cause of global warming?

No. The Sun's influence on Earth's climate is explained here:

Nice evasion.

But, since the far distant future is of no practical import to the here and now, perhaps you'd care to address the question in the current context.
omatumr
1 / 5 (10) Apr 17, 2011
Typo's Corrected:

1. Earth's ever-changing climate is controlled by the Sun:

http://arxiv.org/pdf/0905.0704

2. The photosphere is a glowing cloud of waste products (H and He) from the Sun's central neutron star:

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

3. According to NASA's Dr. Sten Odenwald, the photosphere will eventually expand into a red giant star that extends out all the way "to the orbit of Mercury or Venus or even the Earth!"

www.astronomycafe...958.html
deepsand
3.8 / 5 (16) Apr 18, 2011
Typo's Corrected:

1. Earth's ever-changing climate is controlled by the Sun:


Still evades the question re. the current situation.
deepsand
3.5 / 5 (13) Apr 18, 2011
@ geokstr

Cat got your tongue?

Ethelred
5 / 5 (4) Apr 18, 2011
Calenur
ill you PLEASE do something about these ads?
YOU can DO something. And I note that you don't. Not yet anyway.

Give the post a one and then click on REPORT ABUSE click then on yes. And you can do even more. Click on the Spammer's handle to go to its profile then activity to see the other posts. Then open each of the threads and REPORT ABUSE on each of the spammer's posts.

I seem to be one of the few doing this but I am not the only one.

Join the Few, The Proud, The Anti-Spam Corp.

Ethelred
Ethelred
5 / 5 (7) Apr 18, 2011
b.) That will eventually expand "to the orbit of Mercury or Venusor even the Earth!
Based on a theory that YOU don't believe. So why pretend that you do?

The expansion of suns shows that they DO NOT HAVE neutron stars in them. Or iron or whatever other nonsense you are using this week. Neutron star CANNOT expand as the all matter on them would become degenerate.

Still evades the question re. the current situation.
He evades most hard questions. Follow up questions or repeated questions that he doesn't like result in him giving you ones.

Ethelred
deepsand
3.7 / 5 (15) Apr 18, 2011
Still evades the question re. the current situation.
He evades most hard questions. Follow up questions or repeated questions that he doesn't like result in him giving you ones.

Ethelred

Of that I am well aware.

I address him simply to keep him aware of the fact that he does speak with impunity, that his inability and/or unwillingness to engage in rational discourse does not go unnoticed.

His "1s" signal that I've succeeded in getting his attention. :D