Explaining the mystery of the missing sunspots

Apr 05, 2011
The "naked" sun, free of sunspots, as seen during its recent solar minimum. Credit: NASA/SOHO

Sunspots have been observed for about four centuries, since they were first reported by Galileo. Appearing in roughly eleven-year cycles of activity, sunspots are regions of strong and complex magnetic fields which are also home to large releases of energy and furious solar storms. These storms modulate winds of energetic charged particles that cause significant disruption to communications and power grids when they reach the Earth.

Furthermore, the eruption and decay of sunspots and their associated magnetic fields modulate and extra-galactic cosmic rays, quantities that also affect the Earth's climate.

Modeling sunspots and their influences are important goals of solar astrophysics, and today, four hundred years after their discovery, there has been significant progress.

The number of sunspots at any given time changes during a cycle. The minimum in the last one, numbered Cycle 23, was striking, however: the sun entered the quietest period it has had in 100 years, spending almost two years (2008-2010) devoid of sunspots.

In a paper in the recent issue of the journal Nature, CfA Andres Munoz-Jaramillo, Petrus Martens, and a colleague explain the unusual extended minimum of Cycle 23 in terms of the surface flow of hot material from the sun's equator towards its poles (and its counter-flow deep inside the sun).

They find that a more sophisticated accounting of these flows of material can explain the main characteristics of this extended minimum.

In particular, they argue that a faster flow at the beginning of the Cycle, which slows down after the Cycle's peak, diminished the strength at the poles and increased the number of days without sunspots.

The new results are a significant advance in our understanding of a dramatic phenomenon that has been well-known but mysterious since the time of Galileo.

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User comments : 6

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3.4 / 5 (5) Apr 05, 2011
Brevity is the soul of wit
no, brevity is the soul of lingerie... (dorothy parker)
2.3 / 5 (3) Apr 05, 2011
"Brevity is the soul of wit"

I *so* much wish Shakespeare had not said that... Can you imagine the number of complicated, long-winded, and ultimately hilarious stories we've missed out on because people have accepted this statement as comic wisdom?
1.8 / 5 (9) Apr 05, 2011
Probably the dense, energetic solar core or its iron-rich mantle generates sunspots.

"Superfluidity in the solar interior: Implications for solar eruptions and climate", Journal of Fusion Energy 21, 193-198, 2003.


With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
2.3 / 5 (3) Apr 06, 2011
We need to drill for oil on the sun sun," Tony Heyward I'm sorry

With kind regards,
Tony Heyward
Former BP CEO
Doush Bag for BP
1 / 5 (5) Apr 06, 2011
We need to drill for oil on the sun sun," Tony Heyward I'm sorry

With kind regards,
Tony Heyward
Former BP CEO
Doush Bag for BP

We could more profitably collect the hydrogen that pours from the surface of the Sun as a neutron decay product:

1. Neutron emission from core
Neutron star => neutron

2. Neutron decay
Neutron => hydrogen

3. Escape in solar wind
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000 hydrogen atoms per year depart in the solar wind
1 / 5 (4) Apr 06, 2011
"We need to drill for oil on the sun," Tony Heyward . . .

With kind regards,
Tony Heyward
Former BP CEO
Doush Bag for BP

Hi Tony,

You have obviously been tossed about by the stormy seas of life.

I urge you to study and memorize the last 18 verses of the second chapter of the Gita for the way to successfully ride these waves: "He lives in wisdom who . . ."

Send me a message [omatumr@yahoo.com] if you have questions.

With kind regards,
Oliver K. Manuel

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