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They could almost certainly detonate a nuclear weapon in Korea or Japan. I’d put even odds on a strike on Guam, but probably not quite capable of hitting Western US.
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Is it possible someone could explain as if to a small child what data can be collected from GPS which shows this effect. I don't understand.
GPS signals go through the ionosphere on their way from the satelites. The ionosphere causes distortions in the signal. If you want to achieve the best navigational accuracy you need to account for these distortions. These distortions are not constant. They change from time to time. There are many different ways to account for them. One of the most accurate solution is to keep a GPS receiver on a well known location.…
GPS being a military technology, I presume those fixed gps stations are only located in US-friendly countries. You wouldn't get that adjustment if you are flying over Russia or China, or any ocean. How much of an error in absolute distance are we talking about here? A few cm or meters or a km?
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They very likely already have that.. they’ve detonated >50kt nukes and have mobile ICBM launchers that have demonstrated rockets with thousands of miles of range. They could almost certainly detonate a nuclear weapon in Korea or Japan. I’d put even odds on a strike on Guam, but probably not quite capable of hitting Western US.
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Earlier quoted context omitted.
GPS signals go through the ionosphere on their way from the satelites. The ionosphere causes distortions in the signal. If you want to achieve the best navigational accuracy you need to account for these distortions. These distortions are not constant. They change from time to time. There are many different ways to account for them. One of the most accurate solution is to keep a GPS receiver on a well known location.…
But what are the moving dots in the animation? Planes, satellites? (seems to move like neither). GPS being a military technology, I presume those fixed gps stations are only located in US-friendly countries. You wouldn't get that adjustment if you are flying over Russia or China, or any ocean. How much of an error in absolute distance are we talking about here? A few cm or meters or a km?
Neither. The stations are in Japan. Imagine a line going from each of those stations to the satellite. Where this line crosses the ionoshpere that spot is what is measured. That is what you have information about. Those spots are the dots.
So you basically see the arc of the Japanese islands projected up towards each satelite which is visible from these stations. When the satelite is low on the horizon this projection seems to move fast, and when it is near the zenit it seems to move slow. This is what you are seeing with the dots.
Their location is calculated here: https://github.com/tylerni7/missile-tid/blob/main/tid/tec.py...
"Given a receiver and a satellite, where does the line between them intersect with the ionosphere?"
And then that is called here: https://github.com/tylerni7/missile-tid/blob/00c5fd25e2ab3c2...
"The locations where the signals associated with this connection penetrate the ionosphere."|
Earlier quoted context omitted.
GPS signals go through the ionosphere on their way from the satelites. The ionosphere causes distortions in the signal. If you want to achieve the best navigational accuracy you need to account for these distortions. These distortions are not constant. They change from time to time. There are many different ways to account for them. One of the most accurate solution is to keep a GPS receiver on a well known location.…
But what are the moving dots in the animation? Planes, satellites? (seems to move like neither). GPS being a military technology, I presume those fixed gps stations are only located in US-friendly countries. You wouldn't get that adjustment if you are flying over Russia or China, or any ocean. How much of an error in absolute distance are we talking about here? A few cm or meters or a km?
I would guess the moving dots are fixed GPS receivers, or more precisely the intersections of lines between fixed GPS receivers and moving GPS satellites with a sphere around Earth representing the ionosphere. If you look at the shape of the moving clusters, some look like Japan.
>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.)
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.
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.)
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