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Mystery of the Sun's Two North Poles
space.com ^ | 23 Apr 03 | Tony Phillips

Posted on 04/23/2003 2:23:08 PM PDT by RightWhale

Mystery of the Sun's Two North Poles

By Tony Phillips Science.NASA.gov

posted: 08:00 am ET 23 April 2003

Three years ago, something weird happened to the Sun.

Normally, our star, like Earth itself, has a north and a south magnetic pole. But for nearly a month beginning in March 2000, the Sun's south magnetic pole faded, and a north pole emerged to take its place. The Sun had two north poles.

"It sounds impossible, but it's true," says space physicist Pete Riley of Science Applications International Corporation (SAIC) in San Diego. "In fact, it's a fairly normal side-effect of the solar cycle." Every 11 years around solar maximum, the Sun's magnetic field goes haywire as the Sun's underlying magnetic dynamo reorganizes itself. The March 2000 event was simply a part of that upheaval. "The south pole never really vanished," notes Riley. It migrated north and, for a while, became a band of south magnetic flux smeared around the Sun's equator. By May 2000 the south pole had returned to its usual spot near the Sun's southern spin axis--but not for long. In 2001 the solar magnetic field completely flipped; the south and north poles swapped positions, which is how they remain now.

Using a supercomputer named Blue Horizon and data from spacecraft (especially NASA's ACE and ESA-NASA's Ulysses) Riley and colleagues are studying how these complex changes can affect our planet. "The Sun's magnetic field permeates the entire solar system," explains Riley. "It interacts with Earth and is the primary driver of space weather."

The vast region of space filled by the Sun's magnetic field is called the heliosphere. All nine planets orbit inside it. But the biggest thing in the heliosphere is not a planet, or even the Sun. It's the current sheet--a sprawling surface where the polarity of the Sun's magnetic field changes from plus (north) to minus (south). "We call it the 'current sheet,'" says Riley, "because an electrical current flows there, about 10-10 amps/m2." The filament of an ordinary light bulb carries sixteen orders of magnitude more amps/m2. But what the current sheet lacks in local amperage, it makes up in sheer size. The sheet is 10,000 kilometers thick and extends from the Sun past the orbit of Pluto. "The entire heliosphere is organized around this giant sheet."

Ordinarily, the current sheet circles the Sun's equator like a wavy skirt around a ballerina's waist. But during the double north pole event of March 2000, the current sheet was radically altered: The waviness increased. Irregularities appeared. Its topology "morphed" from a ballerina's skirt to a giant seashell.

More

(Excerpt) Read more at space.com ...


TOPICS: Culture/Society; Extended News
KEYWORDS: 11yearcycle; 22yearcycle; astronomy; globalwarming; solarcycle
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To: Phsstpok
hid on the 4th planet with the native I had captured

You'd think that somebody who'd never gotten caught smuggling (whether he never smuggled or never got caught) would have been more cautious.

21 posted on 04/24/2003 10:32:12 AM PDT by steve-b
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To: Phsstpok
I'd love to have SciFi start to make Dune mini-series like films out of Known Space tales.

God's teeth! Think of all the material. There is more material for an episodic TV series based on the Known Space stories than there ever was in Star Trek. It would surely be a lot better than the crap that's coming out of the current "Enterprise". I'd be in heaven.

22 posted on 04/24/2003 10:44:24 AM PDT by Bloody Sam Roberts (®)
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To: robertpaulsen
...it's just a lot harder to put baseball cards in the spokes.
23 posted on 04/24/2003 10:49:31 AM PDT by steveo
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To: Bloody Sam Roberts
There is more material for an episodic TV series based on the Known Space stories than there ever was in Star Trek. It would surely be a lot better than the crap that's coming out of the current "Enterprise". I'd be in heaven.

Did you know that Known space has crossed over into the Star Trek universe? A Known Space story, The Soft Weapon, was adapted by Larry Niven for the Star Trek animated series. They substituted the crew of the classic Enterprise for the Pierson's Puppeteer Nessus and two humans, and actually used the Kzinti (!!!). it actually worked out pretty well, story wise. Of course the animation of that show was dreadful.

Since precedent has been set I've often thought of pushing Paramount to license and adapt more Known space stories (changing characters so that the original could still be used stand alone) as plots for Enterprise. They could turn the entire Man-Kzinti wars into the origin of the war with the Klingons! It could fit with the projected story arch of founding the Federation to meet this "new threat." Hell, they could even adapt the stories about early transporters (flash riots, etc.) if they wanted to. Of course Braga, et al, would never go for it. Not invented here!

24 posted on 04/24/2003 3:14:23 PM PDT by Phsstpok
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To: Phsstpok
Oh yes. I remember it well. I always wondered if Niven got any money from that or if it was a ripoff.

I always thought the episode was based on the story "Relic of the Empire" until I did a little more research and found that it was more likely "The Soft Weapon".

I remember when I firstsaw that Trek 'toon. It was all extremely familiar.

25 posted on 04/24/2003 3:25:41 PM PDT by Bloody Sam Roberts (®)
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