Yesterday, sensors detected a major seismic event in North Korea. N.K. said that it had just carried out an underground test of a hydrogen bomb. It was known that N.K. had prepared another nuclear test and was ready to fire it by last March. They were waiting for their leader, Kim Jong-Un, to order the test. Commentators say that he waited until yesterday in order to conduct the test when the U.S. would be involved in a three day weekend for Labor Day celebrations and would be less able to respond. It has also been suggested that Kim was timing the test to be of maximum embarrassment to China, its biggest supporter, which is currently hosting the annual meeting of the BRICS countries (Brazil, Russia, India, China and South Africa).
The previous nuclear test by N.K. was conducted in September of 2016. The regime claimed that they had tested a hydrogen bomb but the international scientific community rated the blast at about twenty kilotons of TNT. This would be consistent with a regular atomic fission bomb test or the failure of a hydrogen bomb test. Once again, the regime is claiming that it tested a hydrogen bomb. What does the scientific community say about this bomb test?
I recently posted an essay about how underground nuclear tests are detected. An underground nuclear test sends out powerful seismic waves that are different than the waves from an earthquake. They are also much shallower.
There is a term called the body-wave magnitude (mB) that is used to measure the intensity of an underground blast. The scale is logarithmic. There is a network of thirty four detectors scattered around the world in the Comprehensive Test Ban Treaty Organization's network that are used to detect underground nuclear tests.
The new N.K. underground test blast was so powerful that it “saturated” the detectors. This means that it exceeded the maximum reading that the detectors were capable of registering. The initial mB esitimations varied widely from different sources between fifty kilotons of TNT and one hundred and fifty kilotons of TNT. There are a number of variables in the equation used for mB and choices of different numbers for type of rock, density, depth, etc. yielded the wide range of the estimate. A subsequent analysis of the possible strength of the mB for a deeper depth than the initial estimations suggested that if the blast went off at a depth of over twenty five hundred feet, it could have been as powerful as three hundred seventy kilotons of TNT. It appears that the North Koreans did actually successfully test a hydrogen fusion bomb.
The successful test of a hydrogen bomb by N.K. is a very troubling milestone in their march to a modern nuclear arsenal. They have been testing missiles that may be able to reach the continental U.S. If they can miniaturize their new bomb so that it can be placed on one of their new missiles, then they would have the capacity to reach and destroy major U.S. cities. The international community has repeatedly said that N.K. could not be allowed to have a nuclear arsenal that could threaten other nations around the world but the North Koreans are close now and getting closer. It is not clear that there is any way to stop them.
Photo from the North Korean Korean Central News Agency of Kim Jong-Un inspecting what is supposed to be a model of the hydrogen bomb that was tested yesterday:
