Satellite data backs theory of North Korean nuclear site collapse

Whether underground cave-ins have made the facility unusable is unknown

satellite image of North Korea's nuclear test site

I SPY  Satellite images and seismic data reveal underground cave-ins at North Korea’s nuclear test site, but it’s unclear whether that has put the facility out of action.

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A new analysis of satellite images and seismic waves from North Korea’s nuclear test site support theories that the underground facility has at least partially collapsed.