From time to time, new ideas come from the planet's space agencies propulsion systems suitable for space travel. Not all of them look good, not even for those with imagination, but some are promising. And if it works, it could speed up our space exploration: both with probes and with human passengers. The main solutions hypothesized at the moment are those based on chemical propulsion or solar sails, but there is a third way that seems increasingly popular: the one that passes through a nuclear energy engine.
From the atom to the cosmos
La NASA funded the startup Positron Dynamics for the development of a new type of rocket engine called FFR (fission fragment rocket engine: nuclear fission fragment rocket). This engine uses the same process as nuclear power plants on Earth, and is capable of producing very high thrust. There are technological hurdles to overcome to make them practical, but the news is that there are two discoveries that can remove them. Here it is illustrated in a presentation.
The first and most important is to incorporate the fuel itself in a special airgel. Aerogels are extraordinarily light materials and incorporating plutonium particles inside them could be the wild card that solves the problem without weighing down the engine structure.
However, aerogels alone would not be able to contain the fission fragments as they break apart. To solve this problem would require a huge external force, and this is where the second solution comes into play: the use of a superconducting magnet. By adding a superconducting magnet to the FFRE, engineers would be able to funnel the fission fragments in the same direction, effectively turning them into a nuclear-powered thrust vector.
Nuclear energy space engine: closer, the next steps
While there are still many hurdles to overcome, the funding provided by NASA shows the US space agency's confidence in a solution like this. In the future, FFREs could become a promising new nuclear-powered propulsion option for space travel. A perfect compromise between the power of chemical engines and the longevity of solar sails?
A really nice trip.