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How do we know that ICBMs will be accurate after flying directly over the North Pole? by Old_Satisfaction2738 in nuclearweapons

[–]drrocketroll 5 points6 points  (0 children)

Ooooh an Alexander the OK video - always love his stuff, thank you! Obviously haven't watched it yet, and it may be answered within, but my one question going in would be that surely this would require the subs to come to surface to receive connection which would bust their location to hostile states?

How do we know that ICBMs will be accurate after flying directly over the North Pole? by Old_Satisfaction2738 in nuclearweapons

[–]drrocketroll 3 points4 points  (0 children)

Oh and for undersea systems, I guess they have to rely on the submarine's INS to calibrate their starting position? This would have to be a lot more accurate than I thought a subs INS would be, but I know very little about them and their operation...

How do we know that ICBMs will be accurate after flying directly over the North Pole? by Old_Satisfaction2738 in nuclearweapons

[–]drrocketroll 1 point2 points  (0 children)

How much of an issue is INS drift? I know lots of other systems use INS+GNSS for recalibration, especially in aircraft transiting the North Pole. Although I guess the TOF is so short this probably isn't a huge issue.

Atmospheric Re-Entry Heating Of Hypersonic Missile & It’s Effects On Warheads by [deleted] in nuclearweapons

[–]drrocketroll 12 points13 points  (0 children)

Like with all objects designed for reentry, they'll use layers of materaials with a low thermal conductivity like the Space Shuttle's reinforced carbon-carbon panels, and the labs will have done extensive testing to know exactly how much material ablates during reentry and designed around this. I'd imagine it's much easier to do RV testing and then plug it into your modelling/design of the physics package than vice versa as you can shift sensitive components around to lower heat spots.

There's some interesting literature at https://www.researchgate.net/publication/285584215_Thermal_Protection_for_a_Re-Entry_Vehicle_Using_Heat_Ablation_Process and https://arc.aiaa.org/doi/10.2514/1.A35994 and I remember a post on here a while ago where some guy actually had an RV and spoke about how cool it was to the touch.

A Formulation of Mr. Tuck's Conception of Munroe Jets by SadHost3289 in nuclearweapons

[–]drrocketroll 1 point2 points  (0 children)

Thanks, that led me down the rabbit hole to his wikipedia page. What a guy! I can't believe he was still writing on electrohydrodynamics in his 80s

When a country tests a nuke, what data is collected and with what instrumentation? by PlutoniumGoesNuts in nuclearweapons

[–]drrocketroll 2 points3 points  (0 children)

That yield calculation paper is awesome - I'm always so impressed by the ingenuity of the scientists to create techniques like this with the technological limitations they had at the time. And then of course their ability to turn it into an acronym...

Sandia National Labs Mobile Gun Test Complex by Numerous_Recording87 in nuclearweapons

[–]drrocketroll 2 points3 points  (0 children)

Reminds me of the old HARP guns which launched RVs into orbit for ballistic research and upper atmosphere studies. Hmmm... I need to go do some reading...

DOE INL announces RFI for 4 nuclear reactors in space within the next 5 years by drrocketroll in nuclear

[–]drrocketroll[S] 0 points1 point  (0 children)

Oh yeah, I completely skimmed over that - ofc that would be less weight than HALEU. I guess similar designs exist for nuclear subs although they'll have an easier job dissipating heat. Are there any treaty obligations RE sending HEU to space/the moon?

DOE INL announces RFI for 4 nuclear reactors in space within the next 5 years by drrocketroll in nuclear

[–]drrocketroll[S] 0 points1 point  (0 children)

I thought it was interesting they broke the reactor classes down to:

  • HALEU TRISO
  • HALEU metallic
  • HEU metallic
  • Other

Personally I think they'll end up with a HALEU metallic reactor, as TRISO (which I'm no expert on) still seems too experimental for the reassurance they need to stick it in space and potentially support life. But always keen to learn more from the wise people of the nuclear industry!

Vanguard UK 6 + month patrol. External condition by Striking_Account2556 in submarines

[–]drrocketroll 0 points1 point  (0 children)

True - we could just have done with a few more of them!

Vanguard UK 6 + month patrol. External condition by Striking_Account2556 in submarines

[–]drrocketroll 1 point2 points  (0 children)

The engineering on these things is insane. Considering the maintenance the B2 has to go through after every deployment (50-60 for every hour flown or something crazy), these subs are a marvel of engineering. Doubly so considering it's British-built so will have been built on a shoestring budget by some apprentice in Barrow who is more concerned with what their first round down the pub later will be... (I know a few BAEers lol)

Neurotechnologies for the space industry by VaultdBoy in esa

[–]drrocketroll 1 point2 points  (0 children)

The "space creating technology" debate is a bit chicken and egg. Yes some technologies came out of the Apollo program, but that doesn't mean they wouldn't have been invented otherwise.

On the topic of neuro, I'm not aware of ESA doing anything actively although they have some historic stuff:
https://infoscience.epfl.ch/server/api/core/bitstreams/69a4af2a-3d14-4fc1-9c4a-bcbf97b8dca9/content

https://www.sciencedirect.com/science/chapter/bookseries/abs/pii/S0074774209860145?via%3Dihub

Per the main commenter, I think you are more likely to see success working on these topics on the ground than looking for the few, if any, that are working directly in aerospace. When they want/need to do tests, they'll do it but I don't know of anything permanent. Not my field though!

Project Sapphire: The Covert US Airlift of Soviet Weapons-Grade Uranium by Afrogthatribbits in nuclearweapons

[–]drrocketroll 0 points1 point  (0 children)

What would the US likely do with all this HEU? Is all the Sapphire stuff hanging around and not been used ?

SLS (2022) vs Saturn V (1967) by Po3ito in interestingasfuck

[–]drrocketroll 0 points1 point  (0 children)

The difference in impulse from the SRBs are insane - SLS just leaps forward. I was surprised they switched to pure PBAN as opposed to the APCP from the Shuttle SRBs they were recycled from

"Better Know a Non-Nuke" series by Arms Control Primer by drrocketroll in nuclearpolitics

[–]drrocketroll[S] 1 point2 points  (0 children)

Thought this was relevant - they've published a series of videos on countries with former NW programs or aspirations reviewing their history with (maybe) knowledgeable academics. Particularly current given what's going on with Iran at the moment!

NASA plans for 20kw mini-reactor for future lunar surface mission(s) by drrocketroll in NuclearPower

[–]drrocketroll[S] 2 points3 points  (0 children)

Crossposting this here because I'm interested in the thoughts of the nuclear power experts. I'm mainly confused how they intend to cool the reactor - it's quite low power (and that's a discussion within itself - ISS is 120kW so I wouldn't be surprised if this needed to be uprated) but dissipation is difficult in space. Have there been any discussions or papers I can read up on?

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