Something weird seems to be happening in the heavens. This week marks a coincidence of the full moon and the summer solstice. Some astronomers are calling this combination of maximum moonlight and the Northern Hemisphere’s longest day a rare event.
It comes close on the heels of last month’s rare passage of Mercury in front of the sun, September’s rare pairing of a lunar eclipse with a so-called supermoon, the rare 2014 “tetrad” of lunar eclipses, the rare 2012 transit of Venus, and a plethora of once-in-a-lifetime planetary alignments, one earlier this year, one in 2014 and one in the summer of 2013. Next year there will be a rare total eclipse of the sun.
If these sorts of events are so rare, why do they happen so often?
Ask a statistician. David Hand, a professor at Imperial College London makes sense of world’s abundance of rare events in his 2014 book, “The Improbability Principle: Why Coincidences, Miracles and Rare Events Happen Every Day” . . .
The fact that astronomers could present either the event or its absence as noteworthy makes some sense in light of what Hand calls “the close-enough effect.” This effect comes into play in news stories about people who win the lottery more than once, he said. Often one “win” is really a more commonplace second and third prize. The more you relax the definition of winning, the greater the odds it will happen twice. (Read more from “Why Extremely Rare Events Keep Happening All the Time” HERE)