A North Korean nuclear test conducted in 2017 was so powerful that it moved the surface of Mount Mantap, the test location, as the explosion was 17 times more powerful than the bomb that destroyed Hiroshima.
A three-member team of Indian Space Research Organisation (ISRO) comprising K.M. Sreejith, Ritesh Agarwal and A.S. Rajawat published their research paper in the Geophysical Journal International.
According to the researchers, the nuclear explosion resulted in sizeable surface deformation while the flanks of Mount Mantap experienced displacements of up to 0.5 metre along the line-of-sight of Japanese satellite ALOS-2.
Based on the satellite data, the researchers predicted that the explosion yield was about 245 to 271 kilotonnes as compared to the 15 kilo tonne bomb used on Hiroshima in 1945.
As there were no seismic data, the researchers looked up to the skies to use the satellite data to measure the variations of the test site surface.
The researchers used the synthetic aperture radar (SAR) data from the Japanese satellite ALOS-2.
According to the researchers, the explosion test was done at a depth of 542 metre below Mount Mantap.