The Atomic Age

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On the afternoon of December 2, 1942, the Atomic Age began inside an enormous tent on a squash court under the stands of the University of Chicago's Stagg Field. There, headed by Italian scientist Enrico Fermi, the first controlled nuclear fission chain reaction was engineered. The result -- sustainable nuclear energy -- led to creation of the atomic bomb and nuclear power plants -- two of the twentieth century's most powerful and controversial achievements.

The 70-year anniversary of this event will be on Sunday, December 2, 2012.

How should we observe this event?

Should we observe it at all?

I am split on the issue. I think we should observe it and celebrate the advance in tehnologies and understanding but also take time to review our progress on these issues.

Maybe we could look ahead to nuclear fusion from now on.

Fusion as a source of energy is a pipe dream because it is extremely expensive, completely non-renewable(fission can be renewable using breeder reactors), and inefficient. The energy requirements to produce hydrogen fuel, as well as the massive demand for lithium it will create, will drive the cost up unacceptably high. In fact, as a long term energy source it has the potential to deplete most of the hydrogen on Earth which is mainly in the form of water and in Organic materials. Not to mention the fact that it may very well use up all of the producible lithium in the Earths crust in only half a century!

Do you have any idea how much water we have on Earth? The oceans cover more surface area than land. How deep is it on average? I don't know either, but it isn't shallow.

Of course, to use it at all, we'd have to have an efficient fusion process, and we don't.

not to mention that the helium can be used in fusion as far as i can tell, thus you are only creating a more powerfull fuel.
that is a lot harder than d-t d-d reactions.

if one could use a pure helium helium reaction there wouldnt even be any neutron radiation and the energy is released directly into the electromagnetic field holding it, meaning no expensive lithium mantle or ineffective thermal power generation.

Did you know that in 1,700,000,000 B.C. (Approximate Year), a series of natural, sustained nuclear fission reactions occured in uranium deposits beneath what is now Oklo, Gabon, on the continent of Africa?

Apparently, the natural nuclear reactor formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a nuclear chain reaction took place. The heat generated from the nuclear fission caused the groundwater to boil away, which slowed or stopped the reaction. After cooling of the mineral deposit, the water returned and the reaction started again. These fission reactions were sustained for hundreds of thousands of years, until a chain reaction could no longer be supported due to depletion of the uranium-rich minerals.

Yet another reason to exploit the Moon. The Moon is thought to be loaded with Helium 3.

ruveyn

We should definitely exploit the Moon! First, it's easier and quicker to get to than Mars. Second, we've already been there, so we know what to expect, Third, we know that there is water, which can be broken down into hydrogen (fuel) and oxygen (air).

(I'm using "We" in the culturally collective sense.)

The far side is shielded from Earth's radio noise, so a SETI site can be set up there without interference from terrestrial radio sources.

Once a lunar industrial base is up and running, a ship launched from the Moon to Mars takes less fuel, both because the Lunar gravity is less, and because the ship's infrastructure would not have to be built to withstand a "blast-off" from the Earth's surface. Of course, the same effect could be achieved by building the ship in Earth orbit, but launching the materials from the Moon to a LaGrange point would take less fuel than launching the same materials from Earth.

isnt there helium 3 in the topsoil on the moon?
deposited there by the solar wind as far as i can gather, (working theory it seems) kind of like a moon sized natural buzzard ram scoop.

we will have the largely electrically driven vasimr moon tug in 2-4 years at the latest(well that is their timeframe for a prototype anyway)
perhaps one should focus on actually getting fusion to function in any way shape or form, the most realistic in my opinion at the moment is pulsed fusion akin to the research at NIF.
their latest status reports showed quite a bit of progress in attaining the required energy densities for long enough.

the largest challenge is repeating it fast enough to actually produce a workable amount of energy, considering the target size is less than a millimeter across, i wonder if it will ever break even with that fuel amount.

As a matter of fact I did. Moreover, I have always wondered if the heat being produced inside of the Earth is the result of the fissioning of Uranium. The process which was initiated by U235 during the first 1,000,000,000 years and is sustained by thorium absorbing neutrons and being transmuted into Uranium; making the interior of the Earth a geological breeder reactor.


As fas as fusion is concerned, 3 decades of active research into thermonuclear fusion as a source of power have shown that fusion consumes more energy than it produces. I've never heard of laboratory fusion of elements heavier than hydrogen as this requires extremely high densities that are found only in Stars. Stellar fusion is energy efficient because of the large mass these objects have creates gravitational potential energy that initiates the reaction.

helium helium fusion have been demonstated in a lab.

as for fusion producing less energy than required to initiate the reaction, that is true for all tokamaks and some other systems.
for the tokamaks its a case of containment and the heat loss through it, the required cooling and support systems are immense compared to even the LHC, ITER's cooling complex is ridicoulous and requires vast amounts of power, the heat you divert form the walls then has to be put back in to maintain fusion, very ineffective.
there is however a lot of pulsed fusion systems where containment is a non issue, or a very limited issue, often just required to improve efficiancy.

one of those system are described here,

it is a variation on the z pinch technique, the aproach is novel and small compared to previous z pinch machines, so small that a complete reevaluationa and implementation of 3 major features is scheduled to take a year, to be done in 2013, already finished one of the harder tasks it seems.

Nonetheless, the cost of producing the fuels required for fusion, be it tritium-deuterium, or even helium-helium, will be exorbitantly high. ESPECIALLY if it has to come from the Moon! Electrolysis of water which can be used to extract deuterium(1 in 2600 water molecules contains a deuterium nucleus)requires very large amounts of energy. Even though it may be possible to initiate fusion that releases more energy than it consumes, the efficiency will be very low compared to fission and reliance on fusion power will drastically increase the cost of energy to levels that are economically unsustainable.

LFTR

The future of nuclear power is not fusion, it is gas phase fission using Tokamak containment reactors. Gas core reactors release more energy than solid core reactors and since they require a magnetic bottle the reaction can be contained and this avoids the danger of a meltdown. Also, if the reaction gets too hot and burning gets out of control, the gaseous fuel delivery valves can be closed whereas in a solid core reactor, it is far too dangerous to remove the fuel rods until the reaction has been stopped.

i dont think anyone is disputing that fisison is cheaper, but it isnt excactly renewable either, the supplies will last far shorter than the available deuterium,
tritium would ideally be bred in fission reactors as a side process to normal operation, that tritium is then fused with deuterium to produce helium that is then turned into energy.

we would need fission reactors anyway, fusion is a decade out in any practical sense at least, from there it will take another decade or two before it becomes truly viable.

also if h-h fusion becomes possible then mining huge quantities of it would become quite cheap, we have the moon adn as long as you find a way to construct drop pods on the moon then the energy required to dump it on earth is relatively insignificant.

sometimes the issue isnt how chepa but how densely you can pack that energy, in that sense fusion, especially he-he fusion has a clear advantage, there is also no neutron radiation from he-he reactions and that will mean that there will be no ionization of the metals used to construct the reactor, so cleanup would be easy and almost tot he point where the mythical nuclear car could become a reality(if it will ever be possible to shrink the tec enough)

thing is i dont think one can simply denounce fusion, it holds a great potential, we should simply stop relying on it as a solution to our current problems and concentrate on using it to prepare for the enxt challenge.

First of all, fission actually CAN be renewable! Ever heard of Breeder Reactors? As it turns out, there is more thorium on Earth than Uranium and thorium can be produced in reactors(along with plutonium and a host of other fissile isotopes). The process of mining Uranium and isotope separation is a HELL of a lot cheaper is terms of money and energy input than heavy water production and particularly the electrolysis of heavy water to produce deuterium. Fusion is cleaner, but will always be more expensive and less efficient.