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eppur_se_muova

(42,493 posts)
7. Thanks for the paper. I knew about the older nuclear interest.
Sat May 16, 2026, 01:07 PM
Saturday
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

Project Orion has been discussed in many books about the history of the atomic bomb, bios of famous physicists involved in the Manhattan Project, space travel, etc. If you'll search old posts in DU you'll find references to the AF's mockup nuclear-powered bomber and nuclear-H2 engines (mostly about the history of these discontinued projects).

One of the odder ideas was to coat a pusher plate with Cf-254, which decomposes mostly by spontaneous fission. The ejected nuclei would be the reaction mass, and since they travel at marginally-relativistic velocities, the potential terminal velocity would be tremendous. The problem, of course, would be in handling such a huge amount of Cf-254.

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Another fucking waste of money. 3Hotdogs Saturday #1
Previous ion engines have favored very heavy atoms as propellant -- mercury or xenon. More atomic mass -- eppur_se_muova Saturday #2
The NERVA engine used hydrogen, so (you know) lithium is heavier than that, but certainly lighter than mercury OKIsItJustMe Saturday #4
Hydrogen is being used there as ejectable mass, nothing more. It's handled by mechanical pumps and pressure. eppur_se_muova Saturday #5
Check out the NASA paper I added to the bottom of the reply OKIsItJustMe Saturday #6
Thanks for the paper. I knew about the older nuclear interest. eppur_se_muova Saturday #7
NERVA was not the same as Orion OKIsItJustMe Saturday #8
Yes, I know that, thank you. In fact you're just repeating things I've already said in my replies. nt eppur_se_muova Saturday #10
We both realize that (I was even repeating myself) OKIsItJustMe Saturday #12
Ah, OK ... writing for a larger audience ... eppur_se_muova Saturday #14
I've been watching "For All Mankind" on Apple TV OKIsItJustMe Saturday #15
Isn't lithium in somewhat short supply? erronis Saturday #3
Meanwhile, at a grossly overspent under intellectual trump supported SpaceX 3825-87867 Saturday #9
NASA is facing serious cuts OKIsItJustMe Saturday #11
More from the paper cited by OKIsItJustMe .... eppur_se_muova Saturday #13
"It must have been a real pleasure to work out the mathematics of MPD for the first time..." OKIsItJustMe Saturday #16
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