The Year The Sun Turned Blue: Inside the 1831 Climate Mystery Scientists Only Just Solved

Nearly two hundred years ago, an event so rare occurred that even the phrase “once in a blue moon” doesn’t quite describe it. The thing is, the Sun turned blue in the sky. The effect of the blue, sometimes greenish, Sun was described by numerous observers around the world throughout the summer of 1831, but no one understood what it was.

Centuries passed – and finally, scientists were able to literally uncover the true cause of this strange natural phenomenon. A “forgotten” volcano, a catastrophic eruption, and even, indirectly, an abandoned nuclear submarine base were implicated here. Intrigued yet? Then let’s read on!

More info: PNAS