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Massive Plasma Waves Sweep the Sun --NASA: "We're seeing things we've never seen before"


A huge storm on the sun this past week unleashed what some have called the most massive eruption of solar plasma ever seen. NASA astronomers said the huge June 7 solar eruption, called a coronal mass ejection, probably wasn't the biggest ever, but it is notable both for its size and its odd behavior, as massive  waves of plasma roared off the sun only to rain back down on the solar surface.

"We're seeing things we've never seen before," said Phillip Chamberlin, an astrophysicist at NASA's Goddard Spaceflight Center and a deputy project scientist on the agency's Solar Dynamics Observatory (SDO) satellite. "It's a really exciting event. There are a lot of exceptions to it."

Since scientists know how these waves initiated by a Kelvin-Helmholtz instability they can use this information to help solve an enduring mystery of why the corona is thousands of times hotter than originally expected.

"One of the biggest questions about the solar corona is the heating mechanism," says solar physicist Leon Ofman of NASA's Goddard Space Flight Center and Catholic University. "The corona is a thousand times hotter than the sun's visible surface, but what heats it up is not well-understood. People have suggested that waves like this might cause turbulence which cause heating, but now we have direct evidence of Kelvin-Helmholtz waves."

Ofman and his Goddard colleague, Barbara Thompson, spotted these waves in images taken on April 8, 2010. These were some of the first images caught on camera by the Solar Dynamics Observatory (SDO), a solar telescope with outstanding resolution that launched on February 11, 2010 and began capturing data on March 24 of that year.

That these "surfer" waves exist in the sun at all is not necessarily a surprise, since they do appear in so many places in nature including, for example, clouds on Earth and between the bands of Saturn.

"The waves we're seeing in these images are so small," says Thompson, the deputy project scientist for SDO. "They're only the size of the United States."

Kelvin-Helmholtz instabilities occur when two fluids of different densities or different speeds flow by each other. In the case of ocean waves, that's the dense water and the lighter air. As they flow past each other, slight ripples can be quickly amplified into the giant waves loved by surfers. In the case of the solar atmosphere, which is made of a very hot and electrically charged gas called plasma, the two flows come from an expanse of plasma erupting off the sun's surface as it passes by plasma that is not erupting. The difference in flow speeds and densities across this boundary sparks the instability that builds into the waves.

In order to confirm this description, the team developed a computer model to see what takes place in the region. Their model showed that these conditions could indeed lead to giant surfing waves rolling through the corona.

Ofman says that despite the fact that Kelvin-Helmholtz instabilities have been spotted in other places, there was no guarantee they'd be spotted in the sun's corona, which is permeated with magnetic fields.
"I wasn't sure that this instability could evolve on the sun, since magnetic fields can have a stabilizing effect," he says. "Now we know that this instability can appear even though the solar plasma is magnetized."

Seeing the massive waves suggests they can cascade down to smaller forms of turbulence too. Scientists believe that the friction created by turbulence -- the simple rolling of material over and around itself -- could help add heating energy to the corona.

Hammering out the exact mechanism for heating the corona will continue to intrigue researchers for some time but, says Thompson, SDO's ability to capture images of the entire sun every 12 seconds with such precise detail will be a great boon.

"SDO is not the first solar observatory with high enough visual resolution to be able to see something like this," she says. "But for some reason Kelvin-Helmholtz features are rare. The fact that we spotted something so interesting in some of the first images really shows the strength of SDO."

The Daily Galaxy via NASA/Goddard Space Flight Center

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hello. they just look alike sun clouds, similar to Earth spewing volcanic ash.

Any reason there isn't a video attached? Its pretty spectacular to watch this. Sun had a hiccup:

"MASSIVE PLASMA WAVES SWEEP THE SUN!" "The waves we're seeing in these images are so small," says Thompson, the deputy project scientist for SDO. "They're only the size of the United States."

Small. Not massive. Small. Nice sensationalistic panic-inducing journalism.

Is this a joke!! When the page stop loading I get a blank page! Have I don't something to piss
you off???

@ophu: At the end of the video I link above your post you can see the energy wave. It is massive. This is the largest ejection ever recorded and well worthy of the term 'massive'.

Well, I don't know its the largest recorded, but brief research would make it seem a candidate. Also, a picture for perspective with the Earth (see upper left for earth size):

@smack: Ejection. Not "wave". Ejection. Yes, I saw the video day before yesterday. Still a deceptive headline when the SDO is calling the waves "small". Not "massive". Small.

@ophu: Yes I know the difference. You referred to "wave", so that is what I tried to address. I guess what you're saying is that the CME was massive, but the 'wave' only moderate, is that correct?

If so, I agree, and now see your point regarding the headline.

I don't understand the bit about the plasma wave "only being the size of the USA"? The CME, flare, and wave that emanated are clearly larger than Earth, let alone a continent...

You quote from here:

I believe the reference to the "United States" is something along the lines of seeing fine-grain resolution in the image, not a summary of the size of the plasma wave.

how cool if something had been fired into the sun to cause these folding plasma waves, to temporarily reduce cosmic radiation, and provide relief for our cooking planet.

more realistically the planetary alignment perhaps has direction-ally strengthened electromagnetic fields enough, to bring to the sun's surface, deeper embedded denser compositions of surface fuels, and this may be what to expect on larger context next year, with more planetary alignment, and a darkening of the sun.

This is spectacular and amazing. Should not this cause communication problems on the ground and air? Have not read any comm problems yet. Why there is no video clip? This would be fantastic to see it in motion.

Thanks for this article. I'd also love to see a video :)

the sun?

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