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Fusion the true solar power.
Fission fusion what's the difference
So fission and fusion reactions what's the difference and why should anyone really care? let's begin with fission. In a nut shell it is the splitting of atoms with high powered collisions, a process that rarely occurs in nature. Fusion is the creation of a new atomically heavier element by fusing two or more lighter ones; a process that is and has been occurring naturally for billions of years. Lets break each one down.Like I mentioned above, fission occurring naturally is quite rare mainly due to the many factors having to be present for a sustained fission reaction. The proper fissionable elements must be present and also, water. Why water? Well fissionable elements are ones that are what we call radioactive meaning that they are giving off high speed particles in a decay process. These particles are moving very fast. Here comes the need for the water. It actually slows the particles down enough to have a self sustaining reaction. One particle hitting another and sending that particle on to hit another rather than just flying off into the surrounding space. Fusion, however is occurring and has occurred and will continue to occur for billions and billions of years all throughout our universe. It's the true solar power it powers every star in the cosmos that has ever been or will ever be. There is a technical term for the period we live in; starliferous kind of self explanatory, simply put we inhabit the period of time when stars light the universe. There was a time when there was only darkness and gas. There will come a time when the last star has been created and the clock will begin ticking in earnest for another dark time to arrive. Once this star has burned through its fuel and it's life is over darkness will once again rule the universe. Don't fret though that's so far into the future no human will witness this time.
Scientist agree mostly anyway our universe sprang into existence around thirteen and half billion years ago. From an infinitely dense point called a singularity the how and why this occurred is still being debated, hotly I might add, in the world of theoretical physics all around the world. I personally believe we will never truly know why this occurred. In the young universe there was only gas, mostly hydrogen and some helium. There were no stars, no planets, nothing of what we see today. In fact it took around two hundred million years for the universe to cool enough so that gravity began to exert itself. The very first star was born and we had light spilling out into the darkness for the first time. These first stars were gigantic; many, many times larger than our closest star, the sun. These giant stars fused their fuel very quickly creating all the while heavier and heavier atoms. Think of a union with layers very good analogy of how a star would look if you could slice one in half. This process continues until the element iron is produced. Once this occurs the star is finished iron kills the fusion process. Once fusion, the heart beat of the star has ended, gravity takes over and in less than a second the star collapses in on itself. Resulting in a super nova explosion. It is this super high energy and temperature explosion that creates all the heavier elements than iron. Which explains why those heavier elements such lead, gold, uranium are relatively rare compared the elements from hydrogen to iron. So we have those early stars to thank for our very existence every element that our bodies are built from was created in these early stars or by the resulting super nova. Just a quick note on our star it is a second or perhaps third generation star about half way through its life. It is not going to die in a giant explosion but it will first expand as it loses grip on its gasses then shrink into what's called a white dwarf. It will then simply get cooler and cooler over time and if the outer planets survive they will continue to orbit a ghost till the universe ceases to exist.
So we see that fusion is the most important process with the exception of the big bang itself, to our existence. It may also be our savior and energy source that could allow us travel the local galaxy anyway. Mother nature harnesses fusion easily enough right? Stars fill the sky and in fact we have one ninety three million miles from us is fusing about 400 million tons of hydrogen per second. It has been doing this for about four and half billion years and should continue doing so for another five billion years. So why can't we humans get some hydrogen heat it up and squeeze together and get a fusion reaction? After all like we just read above, mother nature seems to have no trouble whatsoever accomplishing this many times over. Mother nature has something we humans do not; gravity. It takes an enormous amount of material to compress the center to the point where the temperature and pressure is high enough to kick off fusion. There is, however, a way around this and physics has proven it. There are currently several experimental fusion reactors on the planet today. However, the problem all of them have is the energy needed to sustain a reaction for a very small amount of time far outweighs the energy produced. Since we can't reproduce pressures that naturally occur inside stars using gravity, we use light. Light you say? Yep, light actually has a small amount of push behind it far less than one can feel. After all ,we don't walk out on a sunny day and get knocked down by sunlight. But it is there so if we can focus light and direct it into a small area with the right amount of fusionable material, voilà fusion! Sounds easy enough, right? But remember, it takes the combined gravity of a star to ignite and sustain fusion. Our sun comprises approximately 99.9 percent of all the mass in our solar system. So therein lies the challenge. We haven't yet found a way to compress the fuel to start the fusion process that doesn't consume far more power than it produces. I have faith in human ingenuity and I do believe the answer is there. The real question is when will it be discovered? I'd like to believe it will happen in my lifetime but that may be optimistic. Most futurists believe that in the next century or so our technology will catch up to our desire.
Fusion where can it take us?
So fusion is the power source of the universe. If we do indeed overcome the mostly engineering challenges, what will it do for humankind. The benefit that will be felt by most people will be that energy will be abundant, cheap and non polluting. The day that we make the switch, like I said, is at least fifty years away and in all likelihood a century give or take a decade, is a blessing. Most people fail to realize our economy is based on petro-chemical production. So we need time to move away from this type of economy slowly so we don't have a complete collapse in our economy. If aliens showed up today and gave us the technology putting aside the implications of aliens landing, our whole way of life would crumble. We indeed need time to change the way our economy works in a protracted way not overnight. So we've done it what happens now? The entire world will open up to exploration and habitation. There are many uninhabited areas of our little blue world, mainly because we have no easy way of providing power to these areas. From the highest peaks of the Himalayas, to the incredible landscapes under the seas and lakes. Imagine if you were able to spend a week under the sea with the great barrier reef as a back drop, or the mid-ocean ridges where we find the hot water seeps and vents where some of the most alien type life we have living on the planet. Perhaps spending a weekend at the top of the world where to date less than a thousand people have ever seen. Then you have the rest of the solar system that would open up. Fusion rockets would allow for travel times to be shortened from days to hours to the moon. Mars in as little as thirty days instead of months. The asteroid belt would easily become our source for raw materials needed for further exploration or used back on earth for a myriad of projects and production of goods. The outer solar system is a gold mine of rare earth elements. The atmospheres of the gas giants are loaded in helium 3 which is used as fuel for the fusion reactors. There are at least three moons out there that actually may be inhabited now with at least primitive life. The most exciting of which, in my opinion, is Titan. We have evidence now there may actually be exotic life floating in lakes of paint thinner. Plus, Titan is the only moon that has a thick atmosphere it is actually very Earth-like with the biggest exception being the lack of oxygen. So, one could walk around on Titan with simply a mask for oxygen and warm clothing and explore a world that would seem very foreign but somehow be very familiar. In short, our ability to explore and live anywhere on the planet or our truly amazing solar system boils down to the ability to produce power. Fusion reactors would be the answer to our energy demands and give us the ability to spread across our solar system then to the rest of our galaxy.