Scientists report first findings on key astrophysics problem

Nov 28, 2007

In a paper published recently in the journal Nature Physics, an international team of space scientists led by researchers from the University of New Hampshire present findings on the first experimental evidence that points in a new direction toward the solution of a longstanding, central problem of plasma astrophysics and space physics.

The mystery involves electron acceleration during magnetic explosions that occur, for example, in solar flares and "substorms" in the Earth's magnetosphere - the comet-shaped protective sheath that surrounds the planet and where brilliant auroras occur.

During solar flares, accelerated electrons take away up to 50 percent of the total released flare energy. How so many electrons are accelerated to such high energies during these explosive events in our local part of the universe has remained unexplained.

A mainstream theory holds that the mysterious, fast-moving electrons are primarily accelerated at the magnetic explosion site - called the reconnection layer - where the magnetic fields are annihilated and the magnetic energy is rapidly released. However, physicist Li-Jen Chen of the Space Science Center within the UNH Institute for the Study of Earth, Oceans, and Space discovered that the most powerful electron acceleration occurs in the regions between adjacent reconnection layers, in structures called magnetic islands.

When Chen analyzed 2001 data from the four-spacecraft Cluster satellite mission, which has been studying various aspects of Earth's magnetosphere, she found a series of reconnection layers and islands that were formed due to magnetic reconnection.

"Our research demonstrates for the first time that energetic electrons are found most abundantly at sites of compressed density within islands," reports Chen.

Another recent theory, published in the journal Nature, has suggested that "contracting magnetic islands" provide a mechanism for electron acceleration. While the theory appears relevant, it needs to be developed further and tested by computer simulations and experiments, according to the UNH authors.

Until the UNH discovery there had been no evidence showing any association between energetic electrons and magnetic islands. This lack of data is likely due to the fact that encounters of spacecraft with active magnetic explosion sites are rare and, if they do occur, there is insufficient time resolution of the data to resolve island structures.

In the Nature Physics paper, entitled "Observation of energetic electrons within magnetic islands," lead author Chen reports the first experimental evidence for the one-to-one correspondence between multiple magnetic islands and energetic electron bursts during reconnection in the Earth's magnetosphere.

"Our study is an important step towards solving the mystery of electron acceleration during magnetic reconnection and points out a clear path for future progress to be made," says Chen. UNH collaborators on the paper include Amitava Bhattacharjee, Pamela Puhl-Quinn, Hong-ang Yang, and Naoki Bessho.

Source: University of New Hampshire

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User comments : 9

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earls
1.7 / 5 (6) Nov 28, 2007
"The Myth of Magnetic Reconnection"

http://thunderbol...tion.htm

What am I missing here? Is this a real phenomenon or not? The rest of the Internet seems just as clueless, including Wikipedia.
holoman
2 / 5 (4) Nov 28, 2007
1 hour video on Thunderbolt

http://www.video....16220374&q="thunderbolt

They folks are onto something !
NeilFarbstein
1 / 5 (1) Nov 28, 2007
I think its a real phenomenon
NeilFarbstein
1 / 5 (3) Nov 28, 2007
THEM folks is onto something! Stupid!
earls
2.7 / 5 (3) Nov 28, 2007
I think its a real phenomenon


http://mrx.pppl.gov/

Very informative. I think it adds to the Electric Universe theory instead of being something to oppose. Seems like a miscommunication.
holoman
1 / 5 (1) Nov 29, 2007
Should of read," THESE folks are onto something !"

Neil, please watch the language, if you want anymore of my help !

LearmSceince
2.8 / 5 (4) Nov 29, 2007
"The Myth of Magnetic Reconnection"

http://thunderbol...tion.htm

What am I missing here? Is this a real phenomenon or not? The rest of the Internet seems just as clueless, including Wikipedia.


The essay you site is pseudoscience.
Recently, magnetic reconnection events have been observed around Earth by satellites. Many space craft have measured details of electric and magnetic fields while moving on their trajectories. This hard data contradicts the opening paragraphs of that site.

A general debunking of "The Electric Universe" can be found in a couple places in the Universe Today / Bad Astronomy forums.

holoman
1 / 5 (1) Nov 30, 2007
Any sufficiently advanced technology is indistinguishable from magic.
- Dr. Arthur C. Clark

Great spirits have always found violent opposition from mediocre minds. The latter cannot understand it when a person does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses their intelligence.
- Albert Einstein

Today's science fiction is often tomorrow's science fact.
- Dr. Stephen Hawking

Solar Fusion & Neutrinos
http://www.tim-th...ion.html


Ion01
3 / 5 (1) Dec 05, 2007
The essay you site is pseudoscience.

Why is it that anything which contradict mainstream is called pseudoscience? It is the mainstream science community which must conjure up ideas of dark matter and dark energy which cannot be seen or detected in order to save their failing theories. Yet somehow this is not psuedoscience.