On 4 August 1972, dozens of mines seemed to explode spontaneously from the waters of Hon La, in Vietnam. The weapons had been placed there as part of the Pocket Money operation, a US plan to block North Vietnam from maritime trade during the Vietnam war, and they would have to detonate in the presence of ships. But on that summer day in 1972, US troops flying overhead did not see any vessels that could have detonated landmines.
As reported by Becky Ferreira motherboard, a new study accepted by the magazine Space Weather he proposed a possible solution to this mysterious war event. According to the researchers, the mines were probably triggered by a powerful solar storm, which triggered the magnetic sensors of the mines and led to unexpected explosions.
The new research is based in part on declassified Navy documents, "long buried in the Vietnam War archives," according to the study authors. Navy officials immediately launched an investigation into unexplained detonations, and they soon suspected that solar activity was the culprit.
As Brett Carter explains in the Conversationmany of the mines that seemed to randomly explode were "magnetically influenced mines" designed to detect changes in the magnetic field caused by the passage of ships. In the 1970s it was known that solar activity could disturb the magnetic field here on Earth, but Navy officials wanted to confirm that solar activity could also trigger deeply submerged mines. They consulted with experts from the Space Environment Laboratory at the National Oceanographic and Atmospheric Administration (NOAA) and concluded with a "high degree of probability" that the mines had been triggered by an intense solar storm.
The new study, conducted by Delores Knipp of the University of Colorado, confirms this assessment. In the days before the explosions, the researchers explain, a sunspot region known as MR 11976 has vomited "a series of brilliant flares, energetic improvements of the particles and ejection of earth". A "coronal mass ejection", or a huge expulsion of plasma and magnetic field from the Sun, has reached the Earth in just 14.6 hours; typically, second GizmodoAnd & George Dvorsky, it would take such an event a day or two to hit the geomagnetic field of the Earth. The researchers attribute this speed to two previous impulses, which "zero the interplanetary path" for an ultrafast expulsion.
Northern Vietnam was not the only region affected by this solar storm. Scientists in several locations, including the Philippines, Brazil and Japan, have also noticed magnetic disturbances in the atmosphere. On August 4 and 5, 1972, the American and Canadian power companies reported power cuts that went from minor to serious, and there were telephone and telephonic interruptions on a cable that connected Illinois and the United States. Iowa.
The researchers say the 1972 event was probably "Carrington-class", referring to a huge solar storm that took place in 1859. During the Carrington Event, which is named after Richard Carrington, the British astronomer who first realized that solar activity could cause geomagnetic disturbances on Earth ", the northern lights were reported to the south to Cuba and Honolulu, while the southern lights were seen up to Santiago, in Chile ", writes Richard A. Lovett of National Geographic. In the United States, sparks burst from the telegraph equipment, sometimes they start fires.
If such an event occurs today – when our lives are so tightly connected to technology – the results could be catastrophic, causing mass power loss and interruptions in GPS and satellite communications. So using modern modeling to better understand solar storms, like the one in 1972, could help us prepare for similar events in the future.
"In our opinion," the authors of the study conclude, "this storm deserves a scientific review as a major challenge for the space weather community".
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