I’m sorry for the long pauses in between posts, I’m busy with my third year in secondary school and I simply do not have as much time to write these posts anymore. This year i will be participating in a lot more activities (Science Mentorship Programme, completing my novel etc.). Blogging has been really fun and i really wish that i can make time to do more of these blogs. However, it’s really tough to pull myself to blog after a long day at school. Furthermore i try to make my posts as good as possible and this makes blogging take even more time. In fact i have been working on this very post since mid-December. I will definitely continue to post more, but the frequency of posts will have to be reduced. I simply can’t bring myself to post something that I myself feel is of low quality.
Okay, enough talk, lets get back to the main topic of this post.
I have been thinking about fusion lately after watching a TED video regarding the issue. Fusion has always been something extremely fascinating to me ever since I learnt about it. (and yes, I am going to keep referring to nuclear fusion as fusion.)
When we, as a human race, try to solve engineering problems, we usually turn to nature to give us inspiration. From the minesweeper inspiring tumbleweed to lotus leaves that have inspired us to create hydrophobic surfaces, nature has helped us solve our issues again and again. Fusion is one of those instances where we have taken inspiration from nature, but this time instead of seeking that inspiration from living beings on earth, we have taken that inspiration from the skies.
When we gaze into the sky at night we see stars, hundreds, thousands, even millions of them. When we look into the sky in the day, we see the sun. All these majestic things that fill the sky are all powered by nuclear fusion, the very thing we seek to be able to utilise some day. The intense light and heat coming from the sun and the stars are all produced by tiny nuclei colliding into each other; resulting in part of their mass being converted into energy.
The amount of energy produced is insanely huge. How huge? To answer this question we must look at one of the most famous equations in human history. E=mc^2. E equals m c squared. The energy-mass equivalence formula. Whatever you call it. Developed by the famous Albert Einstein, this short equation reveals the power of nuclear power. Here are the definitions of the terms in the formula:
c- the speed of light
Well if you consider the fact that the speed of light is 300,000,000 m/s (or 300 million m/s) )and after squaring the value you get 90,000,000,000,000,000 (or 90 trillion), you can convert 1 kilogram of mass into enough energy to keep the entire world running for 6 seconds. Well, that ain’t bad considering we burn 9,825,414,830 liters of oil in a day. That’s over 9 billion liters of oil and oil only.
So yes, fusion is powerful. Very powerful. So how does it work? In the stars, intense heat and pressure (and sometimes with a bit of luck), fusion occurs. The heat causes the atoms in the stars to move extremely quickly, this causes the atoms to collide into each other very frequently and with extreme speed and force. The pressure forces them closer to each other, further increasing the frequency of the collisions. With these ingredients, together with some nuclear fuel, the beautiful process occurs, generating large amounts of heat (the energy that is released from the process). PhdComics has made a video explaining the process of fusion.
Fusion makes use of nuclear fuel with small nuclei such as hydrogen and helium. The process can only fuse atoms up to iron. Atoms larger than iron are too heavy to be fused any further. This is opposite of nuclear fission where nuclear fuel with large nuclei are used. After iron, to produce larger nuclei, a supernova has to occur for heavier elements to form.
I recently found this joke on the website SGAG. To those Singaporeans out there, you should probably understand this joke:
The above is in fact true! The reason why supernovas are able to allow larger atoms to form is due to the fact that the force of the explosion generated by the supernova is so great that the iron actually manages to fuse into larger nuclei. Through the explosions of millions or even billions of supernovas, the atoms essential for life were formed.
You could say that you were born from a dying star 🙂
“The most astounding fact is the knowledge that the atoms that comprise life on Earth, the atoms that make up the human body, are traceable to the crucibles that cooked light elements into heavy elements in their core under extreme temperatures and pressures.
These stars, the high mass ones among them went unstable in their later years. They collapsed and then exploded, scattering their enriched guts across the galaxy. Guts made of Carbon, Nitrogen, Oxygen and all the fundamental ingredients of life itself. These ingredients become part of gas clouds that condense, collapse, form the next generation of solar systems, stars with orbiting planets, and those planets now have the ingredients for life itself.
So when I look up at the night sky and I know that yes we are a part of this universe, we are in this universe, but perhaps more important than both of those facts is that the universe is in us, when I reflect on that fact, I look up, many people feel small cause they’re small and the universe is big, but I feel big because my atoms came from those stars. There’s a level of connectivity.”
–Neil deGrasse Tyson (in a TIME magazine interview)
Essentially, why I study physics.
Our current nuclear power plants utilise nuclear fission. The reason for this is due to the fact that fusion is extremely difficult to produce in comparison to fission. Nuclear fission occurs naturally. If you left a block of uranium somewhere, it would literally begin to decay and release energy as heat. However if you leave hydrogen gas alone, it would most definitely not fuse to produce helium.
Stars can make fusion happen relatively easily; they can use their gravitational force to create the high pressures and their already present heat as heat to sustain the fusion. However, the Earth is nowhere near as large or as heavy as a star. To make fusion happen, we utilize multiple methods.
I shall discuss these methods in a future post. I’m sorry i have to cut the post here but i have been delaying this post by a very long time. I hope to release part 2 soon XD.
Clyde Lhui 🙂
P.s I’m still working on a lot of other posts at the same time, these posts will probably take quite a while to complete. Do tell me if you have any suggestions for new blog posts.