A couple posts ago, I briefly touched on the idea of nuclear fusion - the process of merging two light hydrogen atoms to release massive amounts of energy. This concept is awe-inspiring considering our current energy crisis, but it is far from being mastered. A certain nuclear energy source that is utilized, though, is nuclear fission. It's essentially the opposite of fusion - a heavy atom is split, by decay or a nuclear reaction, into two lighter atoms, and a large amount of energy is released.
Now, this process has its proponents and opponents, and I'll get to that in a later post. But here, I'm just going to elaborate on the process of fission and how it is used today.
To split a heavy nucleus requires a good deal of energy. In order to overcome the nuclear force which holds the nucleus in a spherical shape, about 7-8 million electronvolts (7-8 MeV) are needed. This deforms it into a peanut shape, and from here, the two lobes' positive charges allow them to further separate from each other, and two lighter atoms (fission fragments) move away from each other at high energy.
In some cases, 6 MeV of the necessary energy to split the atom is simply acquired by binding an extra neutron to the nucleus. This doesn't work in cases such as Uranium-238, which will sometimes just absorb the neutron and become Uranium-239. How selfish.
The typical output is 200 MeV of energy, which seems like a huge efficiency. How could anyone have an issue with this?
(To be continued, shortly)