Scientists Say They've Figured Out What Turned the Sun Blue

The Sun was feeling gloomy.

Clouded Thoughts

In 1831, a volcanic eruption flooded the skies with so much sulfur gas that it cooled the planet by nearly two degrees Fahrenheit, causing all manner of famine, devastation, and social upheaval.

So gloomy were its effects that, in the northern hemisphere, it even sullied the beaming visage of the Sun, turning it a somber blue instead. In other mood swings, reports from the period say that the Sun also appeared purple and green.

But in the nearly two hundred years since, exactly which volcano blew its top to so shake up the natural order has remained a mystery — until now.

Ashes to Ashes

As detailed in a new study published in the journal Proceedings of the National Academy of Sciences, scientists say they've determined the culprit to be the Zavaritskii volcano on the extremely remote and uninhabited island of Simushir, one of the Kuril Islands, in the Western Pacific.

The breakthrough, according to the authors, came through examining ash found in ice core examples, providing a "perfect fingerprint match" to the Zavaritskii volcano.

"Only in recent years have we developed the ability to extract microscopic ash shards from polar ice cores and conduct detailed chemical analyses on them," study lead author Will Hutchinson, a geoscientist at the University of St Andrews, said in a statement. "These shards are incredibly minute, roughly one-tenth the diameter of a human hair."

The volcano's Kuril Islands are currently controlled by Russia, though Japan disputes its claim to the archipelago. It contains a number of volcanoes — with dozens of them being active — but the sheer remoteness of the islands means many of them remain understudied.

"Finding the match took a long time and required extensive collaboration with colleagues from Japan and Russia, who sent us samples collected from these remote volcanoes decades ago," Hutchin said in the statement.

But the hard work was worth it. "The moment in the lab when we analyzed the two ashes together, one from the volcano and one from the ice core, was a genuine eureka moment," he added.

Climactic Change

In addition to making an impressive achievement in geological forensics, the work is a friendly reminder that many of the world's volcanoes remain unmonitored, including those on the Kuril islands — despite being an extremely productive volcanic region, according to the researchers.

That doesn't bode well if we're to prepare ourselves for the worst consequences of a similar global disaster to the one the Zavaritskii wreaked.

"If this eruption were to happen today, I don't think we'd be much better off than we were in 1831," Hutchison told LiveScience. "It just shows how difficult it will be to predict when and where the next big climate-changing eruption will come from."

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