[dontbenebby]

>Missiles make ionospheric disturbances that GPS records. The yellow ripple is the ionospheric disturbance.

Where can I read more about the meta level concept of "isopheric disturbances"? (Because I suspect I'll find this has been done by military intelligence for a long time then rediscovered by so called "arms control" wonks who insist on putting their code into the public domain.)

[krisoft]

The second tweet in the linked thread links to the paper which inspired them:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201...

> who insist on putting their code into the public domain

You say that as if there is something wrong with that.

[InCityDreams]

" /s", spotted on my end.

[dontbenebby]

>You say that as if there is something wrong with that.

So to be clear, you an arms control expert public domaining code that aids totalitarians like Putin and the North Koreans has... "nothing wrong with that"?

Some domain specific knowledge was meant to be esoteric* and there are a variety of better licenses such as CC-non-commercial that allow peaceful uses of the code without allowing it to be used by literally anyone on the planet.

(*Unless you pay the proper fees, of course. But that's not just about money... you have to earn the right to make the purchase.)

[Dylan16807]

I do not feel bad about indirectly aiding them with well-after-the-fact missile trail detection. Why should I? Why should this be difficult to do?

It can be called "military" but it doesn't help with offenses and doesn't really help with defenses either.

[dontbenebby]

>well-after-the-fact missile trail detection.

Sorry, I missed that bit, I thought this could also be used to detect incoming missiles.

I do not want my enemies to be able to detect incoming missiles.

Sorry for posting so angrily.

[kadoban]

To do anything about incoming missiles, you'd need extremely low latency tracking, integrated into whatever system you're using anyway. Not sure exactly you'd be worried about even if this was near-real-time.

[rosnd]

You could probably use techniques like this to rig an early warning system on enemy territory, but there are of course better options.

[thot_experiment]

Wild! I don't think I've ever seen someone who thinks restricting tech like this is actually a good idea. I thought that was just like, crazy government people who don't understand technology.

I'd hoped we'd moved past printing the entire code of PGP in a hardback book in an OCR font but I guess y'all still out here.

[dontbenebby]

I literally had a bronze bust of JFK on my desk on k street.

I’m not a government type unless I’m calling people my long haired opponent ala Hunter S Thompson running for mayor

[ehnto]

> and there are a variety of better licenses such as CC-non-commercial that allow peaceful uses of the code without allowing it to be used by literally anyone on the planet.

I don't have a fully formed opinion on the rest of your comment, however I can definitely point out that software licensing on open source software will not stop a nefarious third party from using it. They're nefarious!

To a practical point though, information asymmetry is powerful in war, but the cat was already out of the bag for this technology as it's in public papers. The code is just an application of information that was already public, they could probably write their own version of the same code based on the papers.

[krisoft]

> code that aids totalitarians like Putin and the North Koreans has

This is false. Putin is not afraid of shining a very bright radar into the sky to know when missiles are about to hit them. That is the standard and reliable way to go about this.

Have you heard about the “woodpecker” signal? It was the transmission of a giant over-the-horizon early warning radar system. It is now defunct, has been replaced by more modern systems, but when it was operational you could receive it basically anywhere on Earth. That is the scale sovereigns play on.

Only people who don’t have the backing of a sovereign state need to go about detecting launches in this circumspect method.

> Some domain specific knowledge was meant to be esoteric

Yes. But this is not that.

> there are a variety of better licenses such as CC-non-commercial that allow peaceful uses of the code without allowing it to be used by literally anyone on the planet

Are you kidding me? :) In the top of your comment you worry, wrongly, about Kim and Putin using the given code. And your suggested solution is to release it under a different licence? :) You think they would care about that?

[Xylakant]

If you follow the thread, there’s a link to https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201... which contains this introduction:

======== It is widely recognized that rocket launches can be an anthropogenic source to trigger traveling ionospheric disturbances (TIDs) by generating acoustic-gravity waves (Afraimovich et al., 2002; Arendt, 1971; Bowling et al., 2013; Calais & Minster, 1996; Chou et al., 2018; Ding et al., 2014; Kakinami et al., 2013; Li et al., 1994; Lin et al., 2014; Lin, Chen, et al., 2017; Lin, Shen, et al., 2017; Noble, 1990). The rocket-induced long-distance propagating TIDs associated with shock/ducted gravity waves and internal gravity waves were observed by using Arecibo incoherent scatter radar (Noble, 1990) and ground-based Global Positioning System total electron content (TEC) observations (Calais & Minster, 1996). Lin, Shen, et al. (2017) first reported the rocket-induced shock waves and concentric TIDs (CTIDs) subsequently using Global Positioning System TEC over California-Pacific region. They suggested that the CTIDs are the manifestation of concentric gravity waves that were originated from the mesopause region. ====

The effect seems to be proven quite a while ago. Using GPS receivers to make that widely accessible seems to be new, but I honestly doubt that military intelligence would rely on that - I’m confident they have more direct methods to detect launches such as (radar) satellites.

[EmilioMartinez]

What does "gravity waves" mean in this context?

[yongjik]

Probably this? https://en.wikipedia.org/wiki/Gravity_wave

Not to be confused with https://en.wikipedia.org/wiki/Gravitational_wave

[teeray]

Ham radio is actually where you’ll find a lot on the subject. “Band conditions” are determined by the amount of ionospheric disturbance present. For example, meteors entering the atmosphere produce a disturbance that can reflect radio—there are ham radio techniques that exploit this to communicate.