Humanity is still <1 on the Kardashev scale. We've got a ways to go. Besides expanding solar deployments on Earth, we need master the use of nuclear energy on Earth and in Space.
In space, energy is used for propulsion, life support, compute, in situ resource utilization, etc. Same as earth, except we are dealing with the extreme environments of space: vacuum, launch, radiation, extreme temperatures and changes. Nuclear energy is well suited because of its extreme energy density allows for low launch cost and high reliability anywhere in the solar system.
The tech is subdivided based on the type and application. Nuclear type refers to how the nuclear bond energy is extracted. Are you utilizing radioisotope decay or nuclear fission?
With radioisotope decay, a sample of material releases energy over time according to its half-life. For example, Plutonium-238 releases energy as it turns into Uranium-234, with half the sample decaying every 80 years. These systems can be very small, but their power output cannot be changed. You can’t throttle it up and down.
A Nuclear fission reactor requires a significant mass of nuclear fuel to achieve a critical mass. But the power can be changed, and the energy density is about 10x higher than a radioisotope decay source. You can turn it off and use it as needed.
As for applications - how will you utilize the energy of the fissions and decays. The most typical way is to convert the thermal energy to electricity using thermo electrics, thermo photovoltaics, or Stirling engines. You can also use a turbine setup like a Helium/Xenon Brayton cycle. You can then use the electricity for whatever you want including electric propulsion.
There are also other more direct ways to produce thrust. For example, you can utilize the thermal energy to directly heat a propulsion gas like hydrogen in a nuclear thermal propulsion engine. Even more directly, you can use the fission products from the fission reactions or decay products as the exhaust to create the desired thrusts.
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Many possibilities will be presented at the ANS Nuclear and Emerging Technologies for Space (NETS) this week in Santa Fe, New Mexico.
If you can't make the conference, please reply with particular sessions or papers you'd like reporting on. Click on a session to see the papers
https://lnkd.in/gb2ZmY9D
