An Intense Solar Storm During the Vietnam War

The following item is based in large part on an article that appeared in Meteored Italy, written by Margherita Erriu on July 2, 2023.  Excerpts from the article will appear in ItalicsIn 1974, I was one of 2,500 recently discharged veterans attending Staten Island Community College and its upper division Richmond College.  I was in the U.S. Army from 1970 to 1971, now reside in Staten Island, New York, and am a longstanding member of the Amateur Astronomers Association of New York.   I volunteered at a peer-counseling program called the Veterans Advisement Center.  At that time, a buddy of mine who was previously stationed at an Air Force base in Thailand told me that, “it’s probably classified, but during the mining of Haiphong Harbor in North Vietnam, our military readiness went to DEFCON 2.”  He speculated that they had probably picked up Chinese Army movements to trigger the classification.  However, last month when I read the Meteored Italy article, I understood what really happened:


A study by the University of Colorado has clarified the mystery of the sudden and instantaneous detonation of dozens of submarine devices (mines) off the coast of Vietnam during the Vietnam War.  On August 4, 1972, in the midst of the Vietnam War, while United States Air Force pilots were flying over the Gulf of Biebu, dozens of submarine mines exploded simultaneously south of the port of Haiphong, in North Vietnam.

Of the three types of the sun's geomagnetic storms, a prominence is the most mild. It is a huge cloud of relatively cool gas that can last months.

Can you imagine what our military intelligence analysts were thinking when they received the pilots report?  Was this a new secret weapon?  Who gave it to the Vietnamese?  Surely, their first recommendation would have been to increase our defense posture.   At the very least, the Strategic Air Command (SAC) would have received the DEFCON 2 order.  This would buy time to figure out what happened.


American pilots stated that at the time no ships were navigating that stretch of sea.  The naval mines had been laid at sea by the United States Navy just 3 months earlier to block the arrival of any supplies to (North) Vietnam.

A solar flare is much more violent than a prominence. These explosions on the photosphere can sweep across an active region in minutes, causing solar material to reach high speeds and blasting the gas into space.

Whether it was because the event was classified, or the government couldn’t come to any decisive proof, the incident remained an enigma until the present.


This was until a research team from the University of Colorado, led by Dr. Deloris Knipp, hypothesized a possible link between the detonation of the mines and intense solar activity recorded around those days.


At the time, Naval mines were activated by magnetic detection from the steel hull of a ship.  Even a small change in the Earth’s magnetic signature caused by a passing ship was enough to explode the mine.

A coronal mass ejection is the most violent of the geomagnetic storms. The ejected matter is a plasma of electrons and protons embedded within the ejected magnetic field.

Dr. Knipp’s research team therefore hypothesized that the mines were detonated by an intense solar storm, which actually occurred and was recorded.


In fact, many astronomical observers at the time noticed that an active region (of the Sun) with numerous sunspots, the MR 11976 region, was…facing our planet.  This very region between 2 and 4 August produced a series of flares with coronal mass ejections directed towards the Earth.


This is reminiscent of the Carrington Event of September 1st and 2nd in1859 (most likely a Coronal Mass Ejection) which shut down telegraph lines and burned telegraph operators.  Lloyd’s of London and the Atmospheric and Environmental Research (AER) estimated that a similar event would cause damages of at least $698 billion to $3.02 trillion in terms of 2021 dollars or roughly 3.6 to 15.5% of annual GDP.

Let’s hope that such an event does not return again to deep-fry our modern-day technology!