The science behind northern lights

Oct 02, 2012 by Marcia Goodrich
The Science Behind those Eye-Popping Northern Lights
Aurora borealis above Keweenaw Bay, near Baraga, Michigan, on Sept. 30, 2012. Credit: Sarah Bird photo

(Phys.org)—Northern night skies have recently been alive with light. Those shimmering curtains get their start about 93 million miles away, on the sun.

An ( in the Southern Hemisphere) is precipitated by explosions on the surface of the sun, sometimes starting as , said Robert Nemiroff, an astrophysicist at Michigan Technological University and coauthor of NASA's Astronomy Picture of the Day website.

These flares release a burst of charged particles, or plasma, into the solar system. When they come our way, they whack into the Earth's magnetosphere, which is made up of its own stream of charged particles. That collision causes particles to break free of the magnetosphere and cascade toward the Earth's , usually traveling toward the poles.

"The aurorae happen when these high- bap into atoms and molecules in the Earth's atmosphere, typically oxygen," Nemiroff said. Light is emitted as part of the reaction.

Those particles can also wreak havoc. "The plasma cloud can cause the Earth's magnetic field to fluctuate," Nemiroff said. "At worst, that can knock out satellites and even power grids."

Aurorae can happen anytime, but it's no surprise they are happening now.

"We are nearing the solar maximum, which is when the sun is at its most active," he said. Solar maximums come around every 11 years, but no one knows why.

"You can have solar flares and aurorae during the solar minimum, but we get more now because the sun's magnetic field is tangled up and poking through the surface, releasing plasma," said Nemiroff.

To see more aurora borealis photos, go to the Michigan Tech Aurora page.

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cantdrive85
1.6 / 5 (7) Oct 02, 2012
All these descriptions of collisions, breaking, "bapping", tangling, poking, bumping, and other mechanical interactions is not at all how plasma interacts. Plasma transfers it's energy electrodynamically by flowing in closed circuits. The aurora isn't cause by particles "bapping" one another, they are created the same way a neon light is created, an electric current with a high enough charge density to cause the plasma to glow. This article is a perfect example of how astrophysicists misrepresent or misunderstand the properties and characteristics of electrified plasma, they are making fundamental mistakes in the assumptions about the behavior of what consists of 99.9% of the universe. Is it any wonder they are continuously surprised and astounded by the observations and why their predictions rarely are confirmed.
ValeriaT
3 / 5 (2) Oct 02, 2012
Plasma transfers it's energy electrodynamically by flowing in closed circuits.
Of course not - but the other ways don't play so well with ideas of plasma cosmology, so you've a tendency to ignore them. For example the Alfven waves are waves of charge (actually a free potential solution of Bloch waves), during which the energy is transferred in form of waves, not via plasma flow.

This is just another of missing parameter problem of plasma Universe model: not only it doesn't enable predict the total amount of plasma content inside the Universe (most of matter remains nonionized) - but it even cannot account to the ratio of energy transferred with plasma in various ways. From these reasons it's freely adjustable model, dangerously similar to string theory and/or ekpyrotic cosmology. It's problem isn't it's wrong conceptually, but the excess of freely adjustable parameters.
ValeriaT
2.3 / 5 (6) Oct 02, 2012
Solar maximums come around every 11 years, but no one knows why
Many people (Charvatova, Landscheidt) already know, why is it so - but this explanation is surprisingly obstinately ignored with the rest of astronomers - despite the coincidence it's quite apparent here. The plasma inside of Sun doesn't circulate around center of Sun, but due the Coriolis force it revolves around center of mass of Solar system, which is influenced just with motion of Jupiter planet. I presume, the mutual positions of another planets (Uranus, Neptune) may cause various irregularities of eleven years cycle, which we experienced recently. Of course, the center of mass of solar system may be influenced with whatever else sufficiently massive object or dark matter cloud, which will penetrate through solar system accidentally, so that the actual source of the recent solar cycle violation remains hidden yet.
ValeriaT
1.8 / 5 (5) Oct 02, 2012
What remains apparent is, that the regular solar cycle is good for Sun and quiet life at Earth in the same way, like the regular stirring of the milk boiled at the stove. If you forget to stir it, then the sudden explosive boil may take place. At the case of Sun the sun spots play a role of bubbles inside of solar plasma and the lack of plasma stirring may lead to "overheating" of the Sun and subsequent explosive eruptions later. This happens when the solar plasma isn't stirred well just at the moment, when the center of mass of solar system gets beneath the surface of Sun due the mutual positions of large planets and/or passing the dense cloud of dark matter through center of solar system.
cantdrive85
1 / 5 (4) Oct 02, 2012
A "wave of charge" is an electric current, I fail to see your point.

I'm not sure what to make of the second paragraph, such as;
"not only it doesn't enable predict the total amount of plasma content inside the Universe (most of matter remains nonionized)"
Although, NASA acknowledges that 99 % of the visible universe is plasma. And the theory is not at all freely adjustable, however the complexity of the magnetohydrodynamics of the plasma make it difficult to model. More research and faster computers will help solving the modeling problems that arise from this complexity.
ValeriaT
1 / 5 (1) Oct 02, 2012
A "wave of charge" is an electric current, I fail to see your point.
It's so-called the displacement current, but it's not connected with any permanent flow of matter.
NASA acknowledges that 99 % of the visible universe is plasma
But most of this plasma is constrained with different forces, than with electromagnetic ones. And because majority of Universe is formed with dark matter, which doesn't interact electromagnetically, the behavior of visible Universe isn't so crucial here. This doesn't mean, that the plasma model cannot get some merit for description of particular phenomena. But the scope of these phenomena is currently difficult to quantify. It's like the string theory: it may get some relevant points under certain scope of parameters - but due the inherent fuziness nobody actually knows, where these points actually are.
ValeriaT
1 / 5 (1) Oct 02, 2012
The case, where the plasma model would fail already is for example the Gregory-Laflamme instability. The fibers of dark matter between galaxies may appear like the plasma currents exchanging the matter between galaxies. But in normal plasma these fibers are naturally unstable and they have a tendency to break itself spontaneously. But the fibers of dark matter do behave like the fibers of high-dimensional non-Newtonian fluid and they tend to coalesce into chains of droplets (of galaxies) along their length in similar way, like the fibers of slime. So we can have a specific example of situation, where the plasma model will not work well even at the qualitative level.
cantdrive85
1 / 5 (4) Oct 02, 2012
First, dark matter is hypothetical, and frankly unnecessary when the magnetohydrodynamic properties of electrified plasma are taken into account. Anthony Peratt has shown with his "Evolution of Interaction of Magnetized, Galactic Plasma" [http://articles.a.../seri/Ap SS/0091//0000019.000.html]
that there is no need for the observed phenomenon to include dark matter for accurate modeling.
It has been shown by the same man the interstellar and intergalactic birkeland currents exist, and can do so over many light years. It is where the instabilities are located where we find galaxies and stars arise.
http://plasmauniv...smic.pdf
http://plasmauniv...esII.pdf
http://plasmauniv...007b.pdf
ValeriaT
2.3 / 5 (3) Oct 02, 2012
Actually the concept Gregory-Laflamme instability is based on the hyperdimensional extensions of general relativity - not on particle matter in common sense. As such it has no analogy in magnetohydrodynamic properties of electrified plasma just because the dark matter lacks the magnetohydrodynamic behaviour, but it exhibits a surface tension and viscosity instead. In other cases the "magnetohydrodynamic properties of electrified plasma" could be replaced with gravitoelectromagnetism, which attributes the gravity field many aspects of charged plasma behavior, but at more realistic distances. And it has more robust support in modern theory, as it requires lower number of experimental parameters.
vidyunmaya
1 / 5 (4) Oct 03, 2012
Let us educate ourselves. What links Sun to earth planet ?How !
Beyond sun, where lies the drive ? How ?
It is not simple logic. Search cosmology Vedas interlinks. Vidyardhi nanduri
Q-Star
2.6 / 5 (5) Oct 03, 2012
The dynamics of the systems which produces the 11 (actually 22 plus/minus) year cycle are chaotic in nature, so why would anyone suppose that slight fluctuations in the cycle occur at times? It will rain next month in Seattle, but on which days depends on a butterfly in Africa.

Oh yeah, I almost forgot, plasma, plasma, plasma, plasma,,,,,

Plasma cosmology is moving in the same direction as steady state cosmology took in the 60's,,,, it leaves more and more of the observed phenomena unexplained. Sorry, but some grand ideas don't stand the test of predictions,,,,,,
Q-Star
3 / 5 (6) Oct 03, 2012
Let us educate ourselves. What links Sun to earth planet? Beyond sun, where lies the drive ?? Vidyardhi nanduri


The drive lies on the road to hell. The links are plasma, best to wear a tinfoil hat. Or an insulated suit.
ValeriaT
1 / 5 (4) Oct 03, 2012
Plasma cosmology is moving in the same direction as steady state cosmology took in the 60's,,,, it leaves more and more of the observed phenomena unexplained
I beg to disagree - the plasma cosmology is old naive model, but the recent observations confirm the steady state Universe model more and more. Which phenomena the steady state cosmology left unexplained?
Q-Star
2.6 / 5 (5) Oct 03, 2012
Which phenomena the steady state cosmology left unexplained?


Well there ya are, and here am I.

1) CMB?

2) Accelerating expansion?

3) The so called "Olber's Paradox"?

4) Near-field galaxies are old, while deep-field galaxies are young?

From what we actually see "hot big bang w/ inflation" is the only thing that fits almost ALL of what we observe. The jury is still out with much current interpretation, that is always the case in science.

"Steady-state" theories have been around longer than "big bang theories", (not as long as the heliocentric model), the observations have moved past that as a viable avenue for progress. It was fine for early 20th century technology & methods, but it's now the 21st century and the new and improved technology & methods have falsified most of the "steady-state" squirming and twisting,, but they still try to wiggle out.

"Steady-state" theorists have to keep refining their predictions to what we might see in the "next few years",,,,

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