On Sept. 1, 1859, the brunt of a solar storm collided with Earth, disabling much of the world’s telegraph system. Sparks reportedly flew from telegraph machines, and the night sky turned an apocalyptic red, causing birds to chirp at what they thought was dawn.
Today, scientists believe that in 1859, Earth collided with a massive number of electrically charged particles shot from the sun, all part of a coronal mass ejection. The episode became known as the Carrington Event, after the amateur astronomer, Richard Carrington, who observed the related sunspots that morning with his telescope.
Ancient Tree Rings Reveal a Solar Storm
As dramatic as the Carrington Event was, it would have paled in comparison to a past solar storm recently detected by an international team. Working in the Drouzet River in the French Alps, the scientists analyzed half-fossilized tree rings cut from ancient tree stumps found in and around the waterway. In the ancient wood, the team detected chemical evidence of a so-called “Miyake” solar storm from 14,300 years ago.
Only nine such extreme storms have ever been identified, with the most recent striking in A.D. 993.
Read More: Are We Ready for the Next Big Solar Storm?
Chemical Evidence of Extreme Solar Activity
The scientists detected unprecedented levels of radiocarbon in the wood, the same chemical used to date ancient materials. When cosmic rays from the sun react with Earth’s atmosphere, they produce radiocarbon, which plants then absorb.
To double-check the finding, the researchers compared the date to beryllium levels – another chemical created by cosmic rays – in Greenland ice cores, and found confirmation.
If a similar storm were to hit today’s world, it would cause destruction on an unimaginable scale. Changes in Earth’s magnetic field would likely damage electrical transformers all over the world, causing months-long blackouts. The storm could also disable GPS and communications satellites, stranding people all over the world.
Partially fossilized tree rings in the Drouzet River. (Credit: Cécile Miramont)
Cécile Miramont
Read More: When North Goes South: Is Earth's Magnetic Field Flipping?
Unpredictable Solar Storms: Planning for the Future
Worst of all, Miyake events are supremely unpredictable.
According to a statement released by the researchers, “We do not know what causes such extreme solar storms to occur, how frequently they might occur, or if we can somehow predict them.”
The team also warns that it’s “critical to understand the future risks of events like this, to enable us to prepare, build resilience into our communications and energy systems and shield them from potential damage.”
Physicist Fusa Miyake of Nagoya University identified the first event named for her in 2012 by analyzing radiocarbon levels in tree rings dated to A.D. 774.
Scientists have since found evidence for several more, but some of those have not yet received independent verification.
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