© NASA
An analysis of recently declassified US military documents confirms suspicions that, during the late stages of the Vietnam War, a powerful solar storm caused dozens of sea mines to explode.
It's a stark reminder of the Sun's potential to disrupt our technological activities in unexpected ways.As part of Operation Pocket Money, the US Navy planted a series of
Destructor sea mines near strategic ports off the coast of North Vietnam. A few weeks later, on August 4, 1972, crew members aboard US Task Force 77 aircraft suddenly observed a batch of explosions south of Hai Phong.
In all, some 20 to 30 explosions were documented in just 30 seconds. Another 25 to 30 patches of muddy water were also observed, indicative of further explosions.
It was a bizarre occurrence, as there was no reason why the mines should have gone off.
Almost immediately, US officials began to contemplate extreme solar activity as the cause, as revealed in newly declassified US Navy documents.
© US NavyDestroyer underwater explosion locations
New
research published last month in
Space Weather, a publication of the American Geophysical Union, agrees with this 46-year-old assessment, while providing new details about this particularly nasty solar storm, which disrupted more than just naval mines.
The study's authors, led by Delores Knipp from the University of Colorado and Brian Fraser from the National Center for Atmospheric Research, Boulder, say the historical event should serve as a call to action.
The bombs that exploded were
magnetic sea mines, a weapon that dates back to the First World War. When a ship passes above, the mine senses a change to the magnetic field density, triggering a detonation. Within days of the August 1972 incident, US military officials began to wonder if solar activity might have been responsible for the unanticipated mine detonations.
Comment: New Executive Order points to devastating space event, unprecedented government response - and public's lack of preparedness