Solar wind energy source discovered

Mar 11, 2013 by Dr. Tony Phillips
Solar wind flows away from the sun at speeds up to and exceeding 500 km/s (a million mph).

Using data from an aging NASA spacecraft, researchers have found signs of an energy source in the solar wind that has caught the attention of fusion researchers. NASA will be able to test the theory later this decade when it sends a new probe into the sun for a closer look.

The discovery was made by a group of astronomers trying to solve a decades-old mystery: What heats and accelerates the ?

The solar wind is a hot and fast flow of magnetized gas that streams away from the sun's . It is made of hydrogen and with a sprinkling of heavier elements. Researchers liken it to the steam from a pot of water boiling on a stove; the sun is literally boiling itself away.

"But," says Adam Szabo of the NASA Goddard Space Flight Center, "solar wind does something that steam in your kitchen never does. As steam rises from a pot, it slows and cools. As solar wind leaves the sun, it accelerates, tripling in speed as it passes through the corona. Furthermore, something inside the solar wind continues to add heat even as it blows into the cold of space."

Finding that "something" has been a goal of researchers for decades. In the 1970s and 80s, observations by two German/US Helios spacecraft set the stage for early theories, which usually included some mixture of plasma instabilities, magnetohydrodynamic waves, and turbulent heating. Narrowing down the possibilities was a challenge. The answer, it turns out, has been hiding in a dataset from one of NASA's oldest active spacecraft, a named Wind.

Using Wind to unravel the mystery was, to Justin Kasper of the Harvard-Smithsonian Center for Astrophysics, a "no brainer." He and his team processed the spacecraft's entire 19-year record of solar wind temperatures, magnetic field and energy readings and ...

"I think we found it," he says. "The source of the heating in the solar wind is ion cyclotron waves."

Ion cyclotron waves are made of protons that circle in wavelike-rhythms around the sun's magnetic field. According to a theory developed by Phil Isenberg (University of New Hampshire) and expanded by Vitaly Galinsky and Valentin Shevchenko (UC San Diego), ion cyclotron waves emanate from the sun; coursing through the solar wind, they heat the gas to millions of degrees and accelerate its flow to millions of miles per hour. Kasper's findings confirm that ion cyclotron waves are indeed active, at least in the vicinity of Earth where the Wind probe operates.

An artist's concept of the Wind spacecraft sampling the solar wind. Justin Kasper's science result is inset.

Ion cyclotron waves can do much more than heat and accelerate the solar wind, notes Kasper. "They also account for some of the wind's very strange properties."

The solar wind is not like wind on Earth. Here on Earth, atmospheric winds carry nitrogen, oxygen, water vapor along together; all species move with the same speed and they have the same temperature. The solar wind, however, is much stranger. Chemical elements of the solar wind such as hydrogen, helium, and heavier ions, blow at different speeds; they have different temperatures; and, strangest of all, the temperatures change with direction.

"We have long wondered why heavier elements in the solar wind move faster and have higher temperatures than the lighter elements," says Kasper. "This is completely counterintuitive."

The ion cyclotron theory explains it: Heavy ions resonate well with ion cyclotron waves. Compared to their lighter counterparts, they gain more energy and heat as they surf.

The behavior of heavy ions in the solar wind is what intrigues fusion researchers. Kasper explains: "When you look at fusion reactors on Earth, one of the big challenges is contamination. Heavy ions that sputter off the metal walls of the fusion chamber get into the plasma where the fusion takes place. Heavy ions radiate heat. This can cool the plasma so much that it shuts down the fusion reaction."

Ion cyclotron waves of the type Kasper has found in the solar wind might provide a way to reverse this process. Theoretically, they could be used to heat and/or remove the , restoring thermal balance to the fusing plasma.

"I have been invited to several fusion conferences to talk about our work with the solar wind," he says.

The next step, agree Kasper and Szabo, is to find out if ion cyclotron waves work the same way deep inside the sun's atmosphere where the solar wind begins its journey. To find out, NASA is planning to send a spacecraft into the sun itself.

Solar Probe Plus, scheduled for launch in 2018, will plunge so far into the sun's atmosphere that the sun will appear as much as 23 times wider than it does in the skies of Earth. At closest approach, about 7 million km from the sun's surface, Solar Probe Plus must withstand temperatures greater than 1400 deg. C and survive blasts of radiation at levels not experienced by any previous spacecraft. The mission's goal is to sample the sun's plasma and magnetic field at the very source of the solar wind.

"With Solar Probe Plus we'll be able to conduct specific tests of the ion cyclotron theory using sensors far more advanced than the ones on the Wind spacecraft," says Kasper. "This should give us a much deeper understanding of the solar wind's energy source."

The research described in this story was published in the Physical Review Letters on February 28, 2013: "Sensitive Test for Ion-Cyclotron Resonant Heating in the Solar Wind" by Justin Kasper et al.

Launched in 1994, Wind is so old that it uses magnetic tapes similar to old-fashioned 8-track tapes to record and play back its data. Equipped with heavy shielding and double-redundant systems to safeguard against failure, the spacecraft was built to last; at least one researcher at calls it the "Battlestar Gallactica" of the heliophysics fleet. Wind has survived almost two complete solar cycles and innumerable solar flares.

"After all these years, Wind is still sending us excellent data," says Szabo, the mission's project scientist, "and it still has 60 years' worth of fuel left in its tanks."

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rubberman
5 / 5 (10) Mar 11, 2013
Awesome research. The more small pictures you have, the easier it is to make the big one.
cantdrive85
2.1 / 5 (14) Mar 11, 2013
Ion cyclotron waves are made of protons that circle in wavelike-rhythms around the sun's magnetic field...ion cyclotron waves emanate from the sun; coursing through the solar wind, they heat the gas to millions of degrees and accelerate its flow to millions of miles per hour. Kasper's findings confirm that ion cyclotron waves are indeed active, at least in the vicinity of Earth where the Wind probe operates.


So...they've figured out that energy can be transported by electric currents, astounding.
Maggnus
4.1 / 5 (14) Mar 11, 2013
That loud 'pop' sound was the sound of the last leg available to the Thunderbolts religious cult disappearing.

Not that their followers won't move the goal posts again. Nor was it much of a leg to begin with.

Nice job by these researchers though! Who says old spcecraft can`t be counted on to produce new science?
cantdrive85
1.7 / 5 (12) Mar 11, 2013
Not surprised by this reasoning from the dogmatic, black is white, up is down, slavery is freedom, and the confirmation of electric currents transporting energy somehow refutes the EUT's understanding of how energy is transported in the galaxy. You were saying something about critical thinking, or your inability to do so...
rubberman
4.8 / 5 (4) Mar 11, 2013
Interestingly enough, this research is serindipedous with the article in the astronomy section where they found that metal rich stars have more violent supernovae. The heavy ions being accelerated in the fashion above would also apply WRT supernova ejecta.
Maggnus
2.6 / 5 (5) Mar 11, 2013
You were saying something about critical thinking


I was indeed! Seriously, despite my contempt of the whole EU religious sect, I actually see some intellegence in you. Read up on it cantdrive, it really is a university level course and it really is interesting. You might start with logical thinking before tackling critical thinking, although I suppose you could go either way with them.

Like I've said to you before, even if you choose to believe the, well whatever you choose to call it, your ability to argue for and defend your position will be greatly enhanced.
cantdrive85
1 / 5 (6) Mar 11, 2013
I actually see some intellegence in you.

And then there was one...
rubberman
3.7 / 5 (3) Mar 12, 2013
I actually see some intellegence in you.

And then there was one...


I have to say I agree with Maggnus CD, so maybe there is two...
As I have mentioned before, sometimes you drop an intellectual bomb that is very logical and well thought out...sometimes you go the other way, but when you do go the "other way" it appears you're echoing someone elses ideas.

brant
5 / 5 (4) Mar 12, 2013
"As solar wind leaves the sun, it accelerates, tripling in speed as it passes through the corona. Furthermore, something inside the solar wind continues to add heat even as it blows into the cold of space."

I think that kinetic velocity is heat....

Magnetic fields do not work as well as electric fields for ion and electron acceleration...
Thats why they use magnetic fields in accelerators and CRT's for beam steering and not acceleration....
rubberman
5 / 5 (1) Mar 13, 2013
Wicked logic brant. Well done. The only way for this NOT to be a factor would be if the plasma was already hotter than the corona.
5 stars from here as well.
cantdrive85
1.8 / 5 (5) Mar 13, 2013
Magnetic fields do not work as well as electric fields for ion and electron acceleration...


The presence and implications of a solar electric field is not something that standard theorists are prepared or willing to consider, regardless of the numerous "mysteries" such a consideration would solve.

"Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century. The conclusion is that astrophysics is too important to be left in the hands of astrophysicists who have gotten their main knowledge from these textbooks. Earthbound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory."
[Lamenting the traditional neglect of plasma physics]
— Hannes Alfvén
Maggnus
5 / 5 (5) Mar 13, 2013
Ah cantdrive, every time I start thinking you can look beyond your preconceptions, you start a rant that suggests you've managed to slide back into the well of ignorance your preconceptions are holding you in.

You do understand that Hannes has been dead for lo these 20 years and that he made this comment in about 1970, right? You do understand that science advances, albeit somewhat slowly, right?

You do realize that the sun has been studied extensively since Alfven's time, right? You understand that at the time Alfven was making these comments, there were few space based solar observatories, right? That no comets or asteroids had been sampled, right?

Get back to the books there grasshopper, you've lost your ability to apply critical thinking to what you are believing so blindly.
cantdrive85
1 / 5 (3) Mar 13, 2013
Plasma physicist Alex Dessler wrote: "When I entered the field of space physics in 1956, I recall that I fell in with the crowd believing, for example, that electric fields could not exist in the highly conducting plasma of space. It was three years later that I was shamed by S. Chandrasekhar into investigating Alfvén's work objectively. My degree of shock and surprise in finding Alfvén right and his critics wrong can hardly be described. I learned that a cosmic ray acceleration mechanism basically identical to the famous mechanism suggested by Fermi in 1949 had [previously] been put forth by Alfvén."

— Quoted in Anthony L. Peratt, "Dean of the Plasma Dissidents", Washington Times, supplement: The World and I (May 1988).

http://www.thunde...-ions-2/

Here we are 60 years later, and his critics still haven't figured it out.
Maggnus
5 / 5 (4) Mar 13, 2013
No cantdrive, his critics actually have figured it out. As have most of the sceintists who found the theory interesting, back in the 80's.

The only people who haven't figured it out are those who read the material from 60 years ago and think they somehow remain relevant today.
HannesAlfven
2.6 / 5 (5) Mar 16, 2013
The Electric Universe is what some education reformers call a "superordinate" concept. Superordinate concepts are general, inclusive concepts which can confer new meaning to all of the less general concepts which they are connected to. According to some education reformers -- like Joseph Novak and David Ausubel -- "the acquisition of powerful superordinate concepts should be a primary goal of effective science teaching" (page 7, Assessing Science Understanding: A Human Constructivist View). More simply, just as artists can become better artists by exposing themselves to a wide variety of artistic expressions, scientific thinkers can similarly strengthen their explanatory skills by cultivating a broad awareness of superordinate concepts such as the Electric Universe.

For those that seem confused, to cultivate a deep understanding of what the EU is, is nothing more than bolstering one's inferential capabilities. But, to argue for ignorance is really just a losing proposition.
Whydening Gyre
1 / 5 (2) Mar 16, 2013
Awesome research. The more small pictures you have, the easier it is to make the big one.

This is what I have been saying all along with my "bigger picture" statements. So... why do I get slammed by Q-star for it (as weak, sophistic "gobbledy-gook")and "1"ed by Lite and you get "5"ed by those same people???
Is it my breath or deodorant?
HannesAlfven
3 / 5 (4) Mar 16, 2013
Re: "No cantdrive, his critics actually have figured it out. As have most of the sceintists who found the theory interesting, back in the 80's ... The only people who haven't figured it out are those who read the material from 60 years ago and think they somehow remain relevant today."

Spoken as if there haven't been any new, surprising observations since the 1980's ...

Those who insist upon viewing the EU as pseudoscience, and who attempt to argue that we should only construct one single paradigm in science, appear to have minimal regard for critical thinking, because when people spend so much time pleading for others to be ignorant of a large set of inferences, they spend that much less time worrying about the philosophical problem of unconceived alternatives.

More simply: There is value to promoting the learning of ideas which we perhaps don't even believe ourselves, insofar as it broadens our inferential skills. Otherwise, how will you know how well the theory is performing?