Gregory Sams, Author of the Month for September 2009
Bring back the Sun! (cont.)
By Gregory Sams
Huge bubbles of charged matter carry the photons from the core through the convection zone to the photosphere with a fractal turbulence compared to that of water in a fast boiling kettle. Whilst the density of the plasma at the beginning of the radiation zone is that of gold, by the time we reach the convection zone the density is that of water. It will emerge into the next level in about a week, where the density of the Sun is now far thinner that the Earth's outer atmosphere.
At just 100 -300 km deep, the visible outer surface of the Sun is relatively as thin as an onion skin. The photosphere provides the setting or base for many of the Sun's most visible, intriguing and dramatic features, from sunspots to solar flares, coronal mass ejections to coronal prominences. Isaac Newton was the first to spot sunspots and track their activity. Records have been kept ever since of their cyclical, though inconsistent nature. Solar scientists are still as puzzled as was Newton by their meaning and mechanism, but have noticed enough of a correspondence with coronal activity to believe that they are managed or controlled by the corona. The same is thought to be the case with flares, coronal mass ejections and prominences, each of them fascinating and powerful events that defy any straightforward explanation.
We have rushed through the processes taking place in the five inner layers of the Sun, in order to give more space to the energetic outer level. We have burst forth from the light-producing core and bumbled through the light-processing radiation zone, twisted through the electrical interface layer, bubbled through the seething convection zone and shot out of the photosphere, adding another spark to the Universe. We have not reached the outer levels of the Sun, but already it seems curious to believe that such structured, complex, co-ordinated and sustained activity is all going on by accident with nary a drop of intelligence involved. Were solar scientists to step outside the bounds of their religiously rooted taboo I strongly suspect that they would recognize this complex and energy-rich assembly of active plasma to be another life form to ours, and quite probably a higher one at that.
The temperature of the Sun progressively drops as photons travel from a 15 million degree core to the 5800 degree photosphere. We would expect the temperature to drop even further as we travel outwards from the surface into the coldness of space. But instead the temperature rises - one of many unexplained aspects of solar behaviour. The "atmosphere" of the Sun is so thin in matter content that it would be considered a near vacuum by our standards, but it is rich in energy and activity.
The lower level of Sun's atmosphere, the chromosphere, is populated by what look like long thin needles or jets of red light shooting upward at high speed. First spotted in 1851, they are called spicules, and there have been various theories as to what they are. The big bubbles of the convection zone may be sending sound waves into the chromosphere powering their upward trajectory at supersonic speeds. One must wonder about the purpose of this activity in the system of a living Sun. At the top of the irregular chromosphere the temperature has jumped from 5800 to 20,000 degrees, and at the other end of the wafer-thin transition to the outer atmosphere, the heat runs to a million degrees.
Now we reach the least understood feature of Sun and, perhaps, its crowning glory. The energy-rich and matter-light corona is bigger than Sun's physical "body," stretching two or three million kilometres into space. Temperatures have become hundreds of times hotter, ranging from one to five million degrees K. Why hasn't the heat emanating from Sun's surface just dissipated into the cold surrounding space? Scientists still struggle to understand why this is.
The corona is an invisible electro-magnetic phenomenon, but the power of its activity and associated events are awesome. It only manifests during a total solar eclipse, as even 1% of Sun's light will completely overwhelm that of its corona. What we see at this moment is its eponymous crown-like shape outlined by light released by free electrons streaming off the Sun, excited by the corona's powerful magnetic field lines. Its shape is not constant, changing along with the Sunspot cycle on the photosphere. Whilst solar scientists hold it responsible for many of the Sun's features, they describe the corona as the most mysterious feature of the Sun. Interesting.
Whilst scientists grapple with the very real difficulties of explaining the nature and existence of the Sun's corona, permit me to hypothesize about the possible relevance of this fascinating phenomenon. Perhaps the invisible corona is the most important feature of Sun - that to which all else is geared, and that which is responsible for some of its most far-reaching effects. It is difficult to resist the temptation to compare aspects of a living conscious Sun to our own existence, relating its fusion-reactor core to our own heart or its chromosphere full of spicules to our seeing apparatus. But it is, of course, a completely different nature of being and in some respects one might as well be looking for the nose of a cauliflower or the nipples of a trout.
It does seem reasonable, though, to look for the mind of a conscious Sun and here, I suggest, one need look no further than its corona. Like our own mind, the corona is essentially an invisible extension of the Sun. As with the force lines of a magnet, all we can ever see is the effect of the corona upon particles that are in its presence. Some scientists will no doubt continue to debate the existence of a human mind until tools are developed sensitive enough to register and measure it. In the perfect darkness of a total solar eclipse, does it not seem likely that we are witnessing the image of a mind infinitely more powerful than our own - without the need for any special tools?
We will leave the Sun now, hitching a ride out on the solar wind, a rarefied stream of charged particles that spins from the corona at speeds of 300-900 kilometres per second. As the Sun turns, the solar wind twists into a huge spiralling electro-magnetic bubble called the heliosphere, which holds the entire solar system in its embrace, cushioning its planets from the potentially disruptive effects of cosmic rays. Isn't that thoughtful?