Nitrogen Fullerenes - Powerful Chemistry

wildsurf writes "A post in sci.energy points to recent confirmation of the stable existence of N60 , through supercomputer simulation. Large-scale synthesis of this material could form the basis for tremendously powerful rocket fuel. Here is an in-depth article on the subject. What would you do with a few million liters of this stuff?"

Comments

Economics

[aburnsio.com]

The key is not so much whether you can sythesize N60, since this will probably be possible in the future. The key is the economics of such an operation.

Economics, not pure technology, is what's driving the next generation of space travel. A primary goal of NASA's next generation launch vehicle to replace the shuttle is to bring down costs for moving payload to low-earth orbit. In particular, NASA wants to reduce the current cost of $10,000/kg by an order of magnitude to $1000/kg.

Making this possible will require technological innovations within economic constraints, such as using kerosene fuel or nuclear engines. If you've been following Mars human exploration plans recently, you'll know that methane engines are one of the most promising plans for synthesizing fuel on Mars. In fact, any long-term Mars mission is likely to require some sort of production of fuel from the Martian surface, and methane can be produced quite readily given an external power source such as a nuclear reactor.

Sure, N60 may provide a higher thrust/weight ratio, but then again, so does antimatter. Antimatter/matter combustion, in fact, has the highest thrust/weight ratio theoretically possible given current physics. We can even sythesize and store it, unlike N60, so we're ahead of the game there. And yet, you don't see antimatter engines because the costs are even more astronomical than the thrust/weight ratio. To get enough antimatter to launch just one LEO mission could very well bankrupt the world.

In conclusion, although N60 has promising potential, the future of rocket propulsion is likely to lie with more conventional and cheaper fuels. Hydrocarbons such as methane and kerosene are still the king of fuels.

Re:Economics

[Mt._Honkey]

"Antimatter/matter combustion, in fact, has the highest thrust/weight ratio theoretically possible given current physics."

Given current physics, yes. Just wait a while though, and we'll get Zero Point Energy working. Evidently there may be enough energy in a 1 cm^3 vacuum to boil all the worlds oceans. Much more energy than antimatter, and you don't have to take it with you, as vacuum is rather abundant. I believe that this energy source was featured in 3001: The Final Odyssey.

Here's something related, the Casimir Effect.

Re:Don't hold your breath for zero-point energy.

[notfancy]

Similarly, by the fact that the vacuum near us hasn't decayed, you can make a pretty strong argument for the observed state of vacuum being the lowest reachable state.

Stephen Baxter's novel Manifold: Space toys with the idea that the vacuum is at a metastable level. The book ends with the release of the vacuum to its actual ground state.

I finished it feeling profoundly depressed.

Also Pollution as a Concern

[Valdrax]

Another factor which may halt the adoption of this chemical as a fuel propellant is the pollution involved. Oxidizing pure nitrogen is bound to get you a lot of nitrogen dioxide (NOx) and other related pollutants. While this might be useful for small explosives, the output from launching a space shuttle off of this fuel might be too much for NASA to consider using even if it does become cheaper than current fuels one day.

On the other hand, the infrequency of launches may be such that the overall emission these pollutants compared to that of traffic in a large city may be negligible. Someone with a better grasp on the exact orders of magnitude here would have to tell you.