Mystery as radioactive particle ‘from unknown source’ is found floating over America

Scientists sampling pollution over Alaska found something alarming 4.3 miles up – a single radioactive aerosol particle, containing enriched uranium.

Researchers knew it could not come from any natural source.

The particle, found in August 2016, but detailed in a scientific journal this month, posed a troubling question: where did it come from?

Researcher Daniel Murphy from the National Oceanic and Atmospheric Administration (NOAA) told Gizmodo, ‘It’s not a significant amount of radioactive debris by itself.

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‘But it’s the implication that there’s some very small source of uranium that we don’t understand.’

The particle was rich in Uranium-235 which means it is ‘definitely not from a natural source,’ the researchers say.

The researchers wrote, ‘During 20 years of aircraft sampling of millions of particles in the global atmosphere, we have rarely encountered a particle with a similarly high content of 238U and never a particle with enriched 235U.’

Some analysts believe that the source could be North Korea.

Nuclear energy expert Arnie Gundersen told Environews, ‘North Korea has a small reactor and does have gas centrifuges for slightly enriching uranium 235… It is possible in either creating new fuel or in extracting plutonium from fuel that has already been in their reactor, some enriched uranium escaped and went airborne.’