Scudder makes first observations of process linked to northern lights

Scudder makes first observations of process linked to northern lights
Diffuse gas—called plasma—flows outward from the sun as the “solar wind” and carries with it solar magnetic field lines that become entangled with the Earth's own magnetic field lines. Location of "holes" were detected in indicated pink layers, near Earth. Image courtesy of NASA.

( -- A University of Iowa researcher wants you to visualize a plate of spaghetti when you think of the northern lights.

That's because Jack Scudder, UI professor of and , and his colleagues have reached a milestone in describing how the northern lights work by way of a process called "magnetic reconnection."

The details are contained in a paper published in the June 5 issue of the journal ; however, the process is best imagined as untangling twisted strands of spaghetti.

—called plasma—flows outward from the sun as the "solar wind" and carries with it magnetic field lines ("spaghetti") from the sun.

The entanglement between magnetic field lines (spaghetti) from the sun and other field lines (spaghetti) anchored in the Earth's core occurs when these field lines are brought together by gusts of solar wind.

"In the process of smoothing this entanglement, one or more holes are created that now link field lines, with one originating in the sun and the other in the Earth's metallic core," says Scudder. "This linkage allows charged particles to cross a previously forbidden boundary that separates the Earth's volume from the sun's. The formation of these inter-connections represents a stress reduction. The aurorae are a byproduct of this change in how the strands of spaghetti are connected, since with the hole, charged particles from the sun are now allowed access into the atmosphere below the Earth's magnetic shield."

One result is the beautiful colors of the northern lights. "Most effects of solar weather that have an earthly influence gain entrance through holes of this type that are in place when a solar disturbance hits," Scudder says. "In this sense the sites of reconnection are the 'keyholes' for the intrusion of solar weather into near Earth space.

"After more than 30 years of research, my colleagues and I have announced a milestone discovery in astrophysics—the first experimentally resolved and unequivocal site of collision—less magnetic reconnection, in which magnetic field energy is converted into energetic particles," Scudder says. "When this process occurs, previously separated volumes of space become interconnected by magnetic fields, providing new highways for the prompt interchange of high temperature gases."

Because magnetic reconnection is thought to occur elsewhere in the universe, Scudder and his colleagues are delighted to have observed evidence of a hard-to-see hole.

In astronomical terms, the size of a hole is relatively small—about 1 kilometer in diameter seen at a distance of 57,000 kilometers from the Earth. If magnetic reconnection were occurring on the surface of the sun, at another star, or at a planet in another solar system, scientists would never be able to see it, Scudder says. Consequently, Scudder's work is all the more important because it serves to "bench test," or prove, an astrophysical process that mankind will never be able to directly corroborate in deep space.

In addition to being small, the hole Scudder observed was in constant motion.

Because the hole was in an unknown state of motion relative to the spacecraft, it could have been traversed many times previously without having been detected. To correct for this situation, researchers developed new techniques to reduce the time interval between "snapshots" by a factor of 11 using the same detector and without flying a new detector.

"This 'trick' is like having access to a microscope for the first time to re-examine data that was thought to have been acquired too slowly to find these holes. Resolving these holes in magnetic fields is somewhat similar to looking at stagnant water through a microscope for the first time and seeing the writhing molecular behavior that was only suspected previously," he says.

Scudder and his colleagues were able to observe the magnetic reconnection site in space by using data from NASA's Polar spacecraft and its Hydra, MFE and EFI experiments. Scudder says the process he observed is active not just in creating the , but many other astronomical phenomena as well.

"The experimental documentation of the physical process that enables this phenomenon provides the first support of the prevailing theories for explaining the production of solar flares, x-rays from black holes, as well as the causes of the aurorae that brilliantly light up the polar skies," he says.

The manner in which Scudder and his associates made the landmark observation involved five different comparisons across three independent detectors to reinforce the detection, similar to the teamwork involved in professional sports.

As part of NASA's Polar/Hydra program at the UI, data from three separate experiments were shown to reproduce the extreme signatures predicted by computer models of the process. These signatures were so unusual that nothing approaching their extremes had been recorded in 50 years of space research. Using the largest computer resources at NASA, the National Science Foundation, and the U.S. Department of Energy, the reference computer models solved six trillion equations of motion in order to predict the observations for the three experiments.

By showing scientists what combinations of observations can help identify these regions, Scudder's work will save time and energy for researchers preparing to explore in detail by using NASA's Magnetospheric Multi-Scale (MMS) mission set for launch in 2014.

Explore further

Cluster opens a new window on 'magnetic reconnection' in the near-Earth space

Journal information: Physical Review Letters

Provided by University of Iowa
Citation: Scudder makes first observations of process linked to northern lights (2012, June 1) retrieved 20 October 2019 from
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Jun 01, 2012
Magnetic reconnection is a joke. There is no such thing. Plasma Cosmology explains these phenomenon in terms of Birkeland currents, which develop double layer sheaths. Magnetic fields develop around these moving currents just like every other magnetic field. These sheaths can become z-pinched and break. It is the current sheath that breaks and reconnects. The magnetic field naturally reforms around it. You cannot have magnetism without a moving electric charge. As Hans Alfven pointed out, plasmas are not ideal conductors. You cannot maintain the magnetic field without the originating current.

Jun 01, 2012
It's important that we not forget that laboratory experiments on magnetic reconnection stop working the second that the power switch is flipped off.

Magnetic reconnection is a byproduct of this worldview that we live within a "magnetic universe." But, this is a hollow worldview, to the extent that astrophysicists' ideas about cosmic magnetism are completely muddled by the gravity-based framework which confines their inferences. If they truly cared about Occam's Razor, they would admit that the simplest inference is that magnetic fields which are observed to span all scales of the universe by now are not "fossils", created in some metaphysical event, but are rather the byproducts of electrical currents. That they don't go there is the natural byproduct of their MHD assumptions, which presume that cosmic plasmas cannot sustain an E-field. Yet, we know from the laboratory that plasmas do contain some minute resistance, and hence E-fields can indeed exist.

Jun 02, 2012
You two above are a bliss on this gravity driven world!
Plasma astrophysics and therefore electromagnetism is the main "dynamo" of all structures we see in the universe. From the smalest ones (atoms and molecules) to the biggest ones (cluster of galaxies, super clusters and beyond!).
Finally, I've seen some sense here where I always get a "1" because my comments against this non-sense of dark matter, dark energy, black holes, n dimension spaces, universes in universes, string theories and all Platonic pseudo-science that has poped out in the last 50 years in cosmology and astrophysics (ah, I've forgot to mention red-shift and the space that expands some billions of light years from here but nothing in our Sollar system or even in the Milky way!) All this ad hoc pseudo-science that has absolutely no proof whatsoever but is taken form granted and spread by TV shows and fancy doctors in science behind the cameras; unfortunately.
Alfvén, you are not Hannes!...:)

Jun 02, 2012
As American heads continue to expand so does the universe... inside their heads.

Jun 02, 2012
Can someone explain to me what a "magnetic field line" is made of? My understanding was that they were abstract entities representing strong areas of magnetic field strength, but I guess that is incorrect...

Jun 02, 2012
@ultrabrad: Magnetic field lines are close conceptual relatives to lines of latitude and longitude. Thus, to talk about them as though they themselves are the movers-and-shakers is conceptually questionable.

There are many factors contributing to this approach, including:

(1) The failure to appreciate the importance of conceptual clarity in physics;
(2) The widespread reification of abstract mathematical ideas into real physical space;
(3) The refusal to read papers in journals (like IEEE), where diverging viewpoints are presented on controversial topics;
(4) The refusal to admit that there are errors within the textbooks;
(5) The refusal to portray our knowledge in certain speculative sciences as uncertain, out of fear that the experts might then be confronted by outsiders.

It will be fascinating to observe what happens to these conceptual issues in conventional physics with the advent of Web 3.0 -- the Semantic Web -- when computers will try to sort through the relationships.

Jun 02, 2012
Assuming that these 'holes' appear in localized spots on the Earth's surface, what is their effect on the ground to lifeforms? Is it just a display of lights in the sky or does the solar wind have some concentrated, if short-lived effect? Is it dangerous to be in that specific location? After all our magnetosphere has a protective effect everywhere else except at these spots. surely there has to be some consequences to the surface, perhaps even an opportunity.

Jun 02, 2012
Any idea of switched power is dependent on power being switchable , your points are tautologically incorrect, the basis of switchable power is that power is reversible from a charged source

Jun 02, 2012
Can someone explain to me what a "magnetic field line" is made of?

Let me try... Imagine a bunch of electrons moving through space. Since they are electrically charged, they are compacted by the magnetic field they generate, but repel each other electrically. Make the current fast enough, and the magnetic field will compress the electrons into an extremely fine thread, smaller in diameter than the uncertainty in any individual electron's position.

Now look at the dual of the above. Since there are no magnetic monopoles, you have to use circular (electrical) currents to create a magnetic field that looks like the field of the moving electrons. When you do that the same self-constricting "force" applies to the flowing magnetic charge. Since there are no actual particles to repel each other, any magnetic field will create fine lines of high flux distributed throughout the area where the magnetic flux is.

Jun 02, 2012
Huh? Magnetic field lines are real? Sure. The lines traced out by iron filings around a magnet can be explained without "real" magnetic field lines.* But if you look at a magnetic field passing through a type II superconductor, you can see the holes where the magnetic field passes through the superconductor. At those holes the material becomes non-superconducting where the magnetic field lines pass through. If the magnetic field was smooth, either there would be no holes, or the entire superconductor would be quenched. (That's why type II superconductors are handy for high Gauss magnets. Oh, and "flux pinning" is handy too. That keeps the field lines from moving around, and creating heat in the process.)

The same lines can be seen writ large about the earth. There is a phenomena amateur radio buffs call whistlers. These are caused by electrical currents wrapped around magnetic field lines.

* The iron filings become little magnets that link together north pole to south

Jun 03, 2012
Magnetic field lines are real and composed of photons, the force particles of the electromagnetic force.

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