"earthquakes in north korea" | Hacker News Reader

"earthquakes in north korea"

wolframalpha.com

79 pointsKipper10038 comments

This is public data from the USGS and numerous other sources. Why is it surprising that Wolfram Alpha is using it?

"Detected" or "indexed"?

http://techcrunch.com/2013/02/11/how-the-nuke-from-n-koreas-...

> "After measuring a 4.9 magnitude seismic event tonight, South Korea’s defence ministry confirmed that it was caused by an underground nuclear test. North Korea’s nuclear capability is estimated to be about 2 kilotons."

I'm not sure if this source is confirmed or not, but very interesting...

For point of reference, Little Boy (the bomb dropped on Hiroshima) was 16 kilotons and 90k+ people. I'm sure there are a ton of other factors besides kilotons that determine how destructive the bomb is, but it's a data point to understand the potential magnitude.

Source: http://en.wikipedia.org/wiki/Little_Boy

Terrain has a bigger impact on how destructive a bomb is. Fat Man was 21 kilotons and 'only' killed ~40k people.

This is their third nuclear test and every single one has failed to cross the eight kiloton boundary at least. If this one is a plutonium weapon like the others it suggests that they are having major issues designing or fabricating the implosion lens around the nuclear material. It is quite striking that they keep conducting tests and reducing their usable nuclear stockpile further. It is almost like they don't have the capability to get a reliable warhead.

They have made an official announcement of the test:

http://www.bbc.co.uk/news/world-asia-21421841

I read the comments, but could someone more expert in seismic activity break this down for me?

How does this demonstrate Wolfram Alpha knew about the nuke itself (or could ascertain there might have been a nuke)?

It looks like it just indexed seismic activity. Is it because the measurements are peculiar?

If you put the coordinates into Google maps you get this address:

http://goo.gl/maps/TNfuD

Shame that there's no street view... C'mon Google!!!

Gulag view -- they should smuggle cameras in!

Zoom out a bit and you can see the "Hwasong Gulag."

https://plus.google.com/101019651244056999126/about?gl=us...

The reviews are, well, you know. Welcome to the internet.

So it looks like they're bombing their own nuclear facility.

Tests are typically conducted in vertical shafts, according to the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty (CTBTO). Holes are cut 1 to 3 meters wide and up to a kilometer deep. The atomic devices are assembled on site and placed in the hole, usually accompanied by lead-protected diagnostic canister that contains sensors to record the explosion. The tunnel is then filled with layers of pea gravel, sand and other materials to prevent radioactive material from being released into the atmosphere.

During a test, the explosion energy is released in less than a millionth of a second, according to CTBTO. The temperature will reach about a million degrees within a few microseconds, and shockwaves from the blast, depending on the size, can be detected by seismographs around the planet.

(From time.com)

"Earthquakes North Korea" != "nuclear tests North Korea" any more than "fire San Francisco" == "temperature San francisco"

Except when the seismic signature doesn't look like a natural earthquake.

As you keep zooming out[1] of the location of this nuke, till you see atleast a whole portion of the earth, you will realize that the existence of this nuke (or the concept of where/how it will be used) is unnecessary.

[1]http://goo.gl/maps/TNfuD (Thanks to HN user jonsherrard for the link)

The nuke in question was already used. What's your point?

I like how they hid it on Nuclear Test Road.

I think the name of that road could be user supplied data to Google through that collaborative mapping effort in North Korea. I could be wrong, though.

Yet wolfram alpha isn't quite smart enough to tell that this wasn't really an earthquake but a nuclear test:

http://www.wolframalpha.com/input/?i=nuclear+tests+in+north+...

I checked "earthquakes in the Netherlands" : nothing there

Google news has the one of 8 feb

https://www.google.com/search?hl=en&gl=us&tbm=nws...

That earthquake was smaller, from: http://www.bloomberg.com/news/2013-02-09/gas-rich-groningen-...

> A quake measuring 2.7 on the Richter scale struck the area ...

To see it in Wolfram Alpha you need to add more parameters: http://www.wolframalpha.com/input/?i=earthquakes+in+Netherla...

Misleading title

http://earthquake.usgs.gov/earthquakes/eventpage/usc000f5t0#...

It just says earthquake here (UK), no mention of nuke.

How would one know this is a nuke? Earthquakes happen.

It was pre-anounced.

Nukes have completely different fingerprints than earthquakes.

An example: http://quakesos.sosearthquakesvz.netdna-cdn.com/wp-content/u...

My old geology teacher said that the test-ban-treaty was a huge boon to geologists, since there was now a bottomless pit of money to be used to build seismographs anywhere you wanted to build them.

The USGS compiles seismic hazard maps based on historical data for this very purpose:

http://neic.usgs.gov/neis/bulletin/neic_c000f5t0_w.html

The idea is basically this:

An exploding buried nuke will send energy in all directions, thus the first movement of the ground is away from the epicenter for all measurement stations around.

An earthquake usually comes about because tension between different areas release, and in that case one part of the ground will start their movement away from the epicenter, the other part will start into the direction of the epicenter.

However, one might need measurement stations covering the whole globe to detect it this way.

edit: Hm, I can't find the image that I've seen in a plate tectonics book a year ago, but here's a plot from a model: http://www.wlandry.net/Projects/Gamra If you look at the arrows in light blue, you can see that some point into the direction of the epicenter while some point away, thus it's an earthquake and not a nuke.

Its also interesting that an 'earthquake' also happened on the same spot in 2009 and 2003 as well...

Nothing for "nuclear tests in north korea" about the recent test.

I for one welcome our Korean overlords, although I'm not sure who will be providing food aid in paradise?

So what?

Nuclear tests directed by crazed lunatics are usually worth taking note of.

duly noted.

Wolfram Alpha can't be trusted then.

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