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  • Seriously North Korea, another underground nuclear test?

  • You know we can see you, right?

  • [DNEWS OPEN] [MAIN]

  • Hey hermit kings and queens, Trace here for DNews.

  • So the Democratic People's Republic of Korea, AKA North Korea, has reportedly tested their

  • 5th nuclear device.

  • They want us to know they did it.

  • We know they want us to know they did it.

  • And they know that we know that they want us to know what we know.

  • But how can we know it was a nuclear bomb?

  • We're not just going to take Kim Jong-un's word for it.

  • There's actually an organization called the Preparatory Commission for the Comprehensive

  • Nuclear-Test-Ban Treaty Organization.

  • Or the CTBTO

  • Though technically I guess it should be the PCCNTBTO.

  • Since 1996, the CTBTO has had it's ear to the ground around the world, listening for

  • any rumblings.

  • That's not just a metaphor, they literally have 42 primary and 107 secondary stations

  • around the world monitoring seismic activity.

  • Usually they just pick up earthquakes, but if there's a nuclear test underground, like

  • all the North Korean ones have been, they'll pick up the seismic waves through the earth's

  • crust and mantle.

  • Based on the direction, speed and type of waves each station picks up, the location

  • of the test site can be deduced.

  • But what if the tests are conducted underwater?

  • That scenario has been planned for too, and the CTBTO has an array of 10 hydroacoustic

  • monitoring stations globally.

  • Why only 10?

  • Because sound travels amazingly well under water, particularly 1000 meters down, at a

  • depth known as the Sound Fixing and Ranging channel, or SOFAR.

  • With just a handful of stations, they can still hear nuclear tests in the earth's

  • oceans, even when they're SOFAR away

  • Get it?

  • And if the tests are conducted in the atmosphere, the CTBTO can catch that too.

  • Again the method is to use sound, this time at frequencies so low we can't even hear

  • them, or infrasound.

  • These longer wavelengths travel farther but they still don't move as efficiently as

  • sound in water, so there are 49 infrasound stations in use right now to listen to the

  • breeze.

  • As a bonus, underground tests generate infrasound too, so the data can be combined with the

  • seismographs for more accurate information.

  • You'll notice all these methods of detection have something in common: they can be tripped

  • by non-nuclear means.

  • Volcanoes, earthquakes, and conventional explosions can cause seismic activity and sound waves.

  • There's only one way to know for sure the bomb was an A Bomb:

  • radioactive fallout. When a nuclear bomb explodes, it creates radioactive xenon isotopes. And,

  • because xenon is a gas, it can seep through layers of rock until it reaches the open air.

  • This means that unless tests are conducted deep underwater or underground, the CTBTO

  • can forensically prove when someone tests a nuclear bomb.

  • So then what? Well that's where the bulldog loses its teeth, I'm afraid. The Comprehensive

  • Test Ban Treaty has been signed and ratified by 164 countries but still needs 8 more before

  • it can enter into force. Hence why the organization is still technically called thePreparatory

  • Commissionfor the CTBTO. So currently when a country sets off a bomb, all the rest

  • of the world can really do is wag a finger at it and impose more sanctions for the test

  • that was unsanctioned. North Korea, perhaps unsurprisingly, has not signed or ratified

  • the treaty, but to be fair the USA has signed it but hasn't ratified it either. Still,

  • until every country is on the same page about nuclear weapons, at least the CTBTO has the

  • tools to warn the rest of the world that someone's not being chill.

  • Guys, if you love DNews in English -- gracias! Now, we've got a new sister

  • show, "DNews en Español" -- It's DNews, but in Spanish! Check it out here.

  • In early 2015 North Korea set off what they

  • claimed was a hydrogen bomb, but was it? How is an H bomb even different from an A bomb?

  • Julian covers all that here.

  • What's your stance on nuclear weapons? Inexcusable superweapon or necessary evil?

  • Let us know in the comments, make sure you subscribe,

  • So you get more DNews and thanks for watching.

Seriously North Korea, another underground nuclear test?

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How Do We Detect Secret Nuclear Tests?

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    joey joey posted on 2021/04/03
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