When I first heard of this project I thought it may be the first true nuclear reactor in space. I thought this because the only other use of nuclear power in space comes from RTG’s or Radioisotope Thermoelectric Generators. Which are similar in the sense that they use heat from a radioactive process to create electrical energy but the difference is that a reactor implies a fission reaction. Where the molecules split in half into two halves that contain less mass than they did when they were joined. The excess mass is converted to a significant amount of energy via Einstein’s famous equation, and thus nuclear power is made. Basically, the comparison is between a battery and a gas generator. RTG’s are very reliable and have served the space program well. But it turns out that the flying reactor has been done before. The United States tested a nuclear reactor for 43 days in space in 1965. But the Russians, never to hampered by a pesky thing like industrial safety, have sent 40 of their TOPAZ-II reactors into space.
RTG’s are nice but they will never meet the kinds of energy needs that we will require to go further than the measly 238900 miles we have traveled. But this new reactor may do it. It seems to be a much more polished design than the test projects of the 60’s and later. Designed to (hopefully) be a plug and play power source, exactly what newly immigrated Martians would need.
The design is apparently a slug of uranium-232 contained in a reactor core roughly the size of a paper towel tube. The core apparently uses some kind of thermal or mechanical process to move the control rod meaning that the core regulates itself and can control its own process in the event its control system fails. The core generates heat which is routed via heat pipes into several of what they are calling “sterling generators”. Now, what I know sterling engines to be are mechanical piston engines that are good at turning heat into a rotational force. That would obviously work in this scenario but I would think sending devices into deep space that contain as many moving parts as an internal combustion engine would be a terrible idea. But I’m also assuming a lot of things. Perhaps they have developed a sterling design that does not incorporate any moving parts. They certainly haven’t sent me the blueprints for review.
I think this is great news. But it is just some news right now. There are no missions planned that utilize the engine. I’m sure tests will continue and in a few years time, we will know if this is the new miracle space tech or another slashed budget line item.