The publication cited an analysis by the Central Institute for Meteorology and Geodynamics in Vienna that said that scientists detected radioactive xenon-133 from North Korea’s nuclear test a week prior. The article said that the global network of sensors picked up faint traces of radioactive gas that probably seeped from the underground test, Nature reports.
The analysis said that the detections of the radioactive gas in Russia and Japan provided additional evidence of the nuclear nature of the February 12 test. The article said the radioactivity did not pose a public health risk.
Following the publication of the story, the Vienna-based Comprehensive Nuclear Test-Ban Treaty Organization contacted Nature to say that the Takasaki, Japan-based radioisotope station primarily responsible for the measurement regularly detects xenon-133 from nearby nuclear facilities. After the ZAMG and the CTBTO discussed the analysis, both bodies concluded that the radioactive gas seen in Japan could not directly be linked to the North Korean test.
The ZAMG took down its analysis of the xenon gas release from its website. Nature followed suit by removing the story from its website.
The initial explosion during the February 12 test was picked up by the CTBTO’s seismometers. Most observers estimated that the blast was approximately several kilotons, similar in scale to the bomb dropped on Hiroshima in 1945, Nature reports.