You know what “space weather” is. It occurs when our Sun spews charged particles in the general direction of Earth. They interact with our planet’s protective magnetosphere to cause aurora—those beautiful twisting (mostly) green light shows—visible during the dark Arctic nights of late fall, winter and early spring.
Want to see aurora? So head to the far north, to Alaska … or to London, Portugal and Madrid?
Although aurora are reliably seen only around the Arctic Circle and Antarctic Circle, sever solar storms push the “auroral oval” further south. The stronger the solar storm, the further south the aurora are sighted. Historical reports of unusual auroras over places that normally never see them can therefore be used as a proxy for the study of solar activity before accurate scientific records began.
And on March 6, 7 and 8, 1582 what’s now known as the “great magnetic storm” brought aurora as far south 29° North latitude.
The subject of a new paper that delves into newly discovered descriptions about this “great aurora,” they are a clue to a solar storm that must have been horrifically strong.
If that happened now it could leave vast populations unable to communicate and without electrical energy.
The Northern Lights and Southern Lights occur most frequently between 64º and 70º North and South latitudes.
In the northern hemisphere that typically means between September and March in Arctic Circle—Alaska, northern Canada, Iceland, and Lapland in Norway, Sweden, Finland and Russia.
Colorful Aurora Borealis, Iceland
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In the southern hemisphere that means between March and September in the Antarctica Circle—south of New Zealand over the oceans and in Antarctica, so they’re more rarely observed.
Knowing how often severe space weather events occur is important for a modern technological society like ours because one could knock out electrical grids, communication systems and satellites. However, despite the number of sunspots on the Sun—an indication of solar activity—being counted since the invention of the telescope in 1610, we don’t have much data.
And certainly not enough to tease-out generational trends in solar activity to accurately predict when the next super-strong solar storm is likely to hit.
A strong solar storm on March 13 and 14, 1989 caused a blackout in Québec, Canada, though the most important solar event in recent history was the so-called “Carrington event” in 1859 which disrupted the early telegraph systems of North America and Western Europe. It caused aurora to be see as southerly as 20° North. It’s the most powerful geomagnetic storm known to date and would be catastrophic to our modern society.
So what happened in 1582?
Probably caused by a series of coronal mass ejections (CMEs) on the Sun, for two nights it caused an auroral oval at mid-northern latitudes, which dipped further south on the third night.
It all occurred just before a full Moon, too, which would have lessened the impact of the aurora. This one was big.
Despite the moonlight, strong reddish aurora were sighted over three nights in Zürich, Paris, London, Madrid, and in Évora near Lisbon—at 39º North—from where this text was uncovered by the new research:
“In 1582, on 6 March, a great fire appeared in the sky at the north and lasted three nights.”
In this mock-up you can see northern Lights over Big Ben and London.
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Another eye-witness account from Lisbon reads:
“In March 1582, at 8 p.m. on Tuesday, March 6, something started in the north band of the sky … all that part of the sky appeared burning in fire flames; it seemed that the sky was burning. At midnight, great fire rays arose above the castle which were dreadful and fearful. Everybody went to the countryside to see this great sign.”
There are also records of “reddish and bluish” aurora on the same dates in southern Japan and in China between 29° North and 36° North.
Of course, there weren’t any power grids or satellites in 1582. So aside from some spectacular and truly once-in-a-lifetime aurora observations, this massive once-a-century solar storm was able to pass without incident.
Not so now.
In fact, a 2013 study by Lloyd’s of London and Atmospheric and Environmental Research concluded that a massive solar storm could cost US$2.5 trillion dollars, and its effects could last for over a year.
Massive solar storms are certainly rare. We just don’t yet know how rare.
Wishing you clear skies and wide eyes.
#News | https://sciencespies.com/news/a-great-red-fire-in-the-sky-baffled-people-439-years-ago-this-month-a-repeat-now-could-send-us-back-in-time/
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