Plasma and Invisible Strings

Walter Gekelman's talk was a really interesting and exciting to listen to. He took what could have been an incredibly overwhelming topic and made it approachable and simple. But that did not make any of what he said any less impressive and humbling. Just the sheer scale of what he was describing was so overwhelming to me, so beyond the scope of the every day human experiences. From wavelengths so much smaller than a human eye could ever perceive, to temperatures so extreme that they break apart matter itself, to lengths of time so incredibly short they last less than the time it takes to complete a single thought or breath. In all of these incredible, and somewhat unimaginable, things, there was so much potential, so much action, so much. Its amazing to think about how much of the universe lies outside of what people can experience, let alone fathom.  So much is sitting there waiting to explored, discovered and adapted.  

Source: http://cat.ocw.uci.edu/media/OC08/11004/OC0811004_SunStructure.jpg

The part of his discussion that interested me the most was his explanation of solar flares. I had really only ever heard of them as that, 'flares', with the vague description of the sun's energy somehow flaring up from all of the chemical reactions and fusion occurring on and beneath its surface.  It was really interesting to find out that the 'flare ups' that appear on the surface are actually plasma and that the sun's surface itself is plasma. I knew it was hot, hot enough to cause the fusion of progressively heavier elements (which in and of itself is fascinating), but for some reason I had never thought or heard of it as plasma. I learned in a physics course that right after the Big Bang the entire universe was just a soup of plasma so thick that it was opaque to light, with random particles moving around at incredible temperatures and speeds. That 'soup' was filled with so much potential; it became what we know as the visible universe (I say visible because there are some parts of the universe that we have not even seen yet because light originating from there has not had enough time, in the billions of years that have gone by, to  reach us. Try to wrap your head around that). To me it makes complete sense that a similar potential still resides in stars like the sun (especially in those much larger than our sun, like the one depicted below). After all, stars are what created the elements that became every part of the human experience of the known universe. But there is even more to it than I could have imagined, including things like 'solar twisters' made up of a "mass of plasma [that] was stretched and pulled... by powerful magnetic forces" and had a temperature of "about 2.8 million degrees C (or 5 million degrees F)" (Wall, 2015)!

Source: http://astronomy.nju.edu.cn/~lixd/GA/AT4/AT421/IMAGES/AACHDDZ0.JPG

Source: http://www.nasa.gov/mission_pages/themis/auroras/sun_earth_connect.html

It was even more incredible to realize that this plasma was creating currents that radiate outward. Again, while I had been taught that the sun's 'energy' radiates outward from it, no one had ever described it to me as a current of particles, especially not a current made up from the interactions between various flux ropes.  According to NASA, these particles travel as solar wind, and are either blown past or caught in Earth's magnetosphere.  What results from these particles, depending on the amounts, are the Aurora Borealis and what we call the effects of solar flares, such as cell phone outages. Seeing it embodied in his simulations was rather mesmerizing and interesting to think about.  It really added to the artistic dimension of his talk.

Source: http://reu.physics.ucla.edu/2012/projects/imgs/wg_small.jpg

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References:

Halpern, Mark (10 Oct 2012). "How Large is the observable universe?" In The Cosmos blog. PBS. http://www.pbs.org/wgbh/nova/blogs/physics/2012/10/how-large-is-the-observable-universe/

Larkin, James. Personal Communication. Wednesday, 9 March 2016.

"Nuclear Fusion in Stars: Nucleosynthesis". Enchanted Learning.  http://www.enchantedlearning.com/subjects/astronomy/stars/fusion.shtml

Wall, Mike (9 Sept 2015). " 5-Million-Degree Plasma 'Tornado Rages on the Sun." Space.com. http://www.space.com/30498-solar-tornado-nasa-sdo-video.html

Zell, Holly (21 April 2006). "NASA- The Sun-Earth Connection."  NASA. http://www.nasa.gov/mission_pages/themis/auroras/sun_earth_connect.html