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mvdwoord

So they are strapping a nuclear power plant to a huge vessel of explosive liquids..

Will the first launch be on PPV?

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RTGs have been going to space since the 60s [1].

[1] https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_...

RTGs do not use fission and do not create fission products. Nuclear fuels are harmless in comparison to Strontium-90 and Cesium-137.

Then you are going to love SNAP-10A https://en.wikipedia.org/wiki/SNAP-10A

And the 31 RORSAT reactors https://en.wikipedia.org/wiki/BES-5

There won't be any fission products in the fuel if the chemical launcher fails to take the nuclear payload to orbit. The reactor activates for the first time after the initial orbital launch. The virgin fission fuel is less radiotoxic than RTG fuel.

>The reactor activates for the first time after the initial orbital launch.

So they're going to launch an untested reactor into orbit without even turning it on first? Getting a reactor up and running is hard enough on the ground. I would expect any reactor to have had thousands of hours of testing and tweaking before being placed on the launch pad; that is the process for military boats and we have 60 years of experience in that environment.

> that is the process for military boats and we have 60 years of experience in that environment

Totally different reactor designs.

Even more need for prelaunch testing then. Novel technological designs are harder to grapple and send to production, not less.

These aren't intended to be powerful complex designs like what the navy uses. They're going to be small, simple and low power with as few moving parts as possible. Probably passively cooled, and having just enough plumbing such that propellant is only heated up when the only way for it to go is out the nozzle.

After all, waste heat is much harder to get rid of in space than here on Earth.

For reference, other space nuclear reactor designs NASA has looked into have been in the lower kilowatts in terms of power output.

Space stuff doesn't yet need the power output relative to size of a modern military reactor, the bigger concern is being reliable and providing stable long term power.

Just wait until you hear about SSBN’s…

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