[BuffaloJack]

According the the USGS seismic readings, the NK blast was equivalent to 550 tons of TNT. For comparison, the Nagasaki blast was a 20-kiloton yield.

If you really think about it, NK could have just trucked 550 tons of conventional TNT into that abandoned coal mine and set it off. Who'd know the difference? The world would see them as joining the Nuke Club and nobody'd be the wiser.

[DB]

They've revised that.

Now they're saying 5kT to 15kT. Much, much larger.

[NinoFan]

Thread on Russia's estimate (which is much larger):

http://www.freerepublic.com/focus/f-news/1716147/posts

[Cold Heat]

If you really think about it, NK could have just trucked 550 tons of conventional TNT into that abandoned coal mine and set it off. Who'd know the difference?

We would! We knew the minute it was detonated. Nukes have a particular seismic signature, and we have that.

They simply have not yet released what we know, and they may not. We can play this in many different ways.