Thursday, October 9, 2014

Eclipsed Reality

Tuesday night's "Hunter's Moon" squeezes between Great Northern Mountain and purple clouds
On Tuesday evening, October's full "Hunter's Moon" rose into the purple tatters of a petulant, western Montana sky. A few hours later, the cloud layers conspired to cloak the moon while the Earth's shadow crossed its cratered face - the second lunar eclipse of 2014.

Exactly six months ago, Montana's last lunar eclipse also occurred on a cloudy, full moon night. What are the odds of that?! Ominous omen? Messenger of doom and despair from the sky? No and no. Of course, mountains lift air masses and create clouds, so we expect western Montana to endure more than its share of shady days and nights - especially when I'm trying to photograph something interesting in the sky.

But just a few hours after Tuesday's eclipse, I found myself laying face-down while a well-educated medical person worked at quenching the embers of my old neck injury. It's hard to speak when your face is squashed, especially while paying someone to inflict pain. So when he started wondering aloud about the "end days" because four eclipses in a row will occur on Jewish holidays, I grimaced.

It's true, Tuesday's eclipse fell on the eve of Sukkot, or "Feast of Booths," and the previous eclipse took place on Pesach, better known as "Passover." Lunar eclipses will occur on these holidays next year, too. While this has led to mischief-making in the press by conspiracy nuts and snake-oil salesmen, the rest of us rational people - especially astronomers and photographers - are downright giddy over these heavenly events.

You see, these two Jewish holidays are six months apart, and they always take place on a full moon. And many (but not all) lunar eclipses are also six months apart, and every eclipse also occurs on a full moon. With 2 eclipses and 2 holidays in 12 months, you end up with a 1 in 3 chance of an eclipse landing on one of these holidays. And when one eclipse lands on Sukkot, it isn't unreasonable for the next eclipse to fall on Passover, six months later. (Detailed explanation here.)

The kicker? Not one of these lunar eclipses is visible from Israel.

This is the stuff of basic geometry, not black magic. This cycle of four lunar eclipses - called a tetrad - is normal but uncommon. (Our last tetrad was a decade ago, and the next one will begin in 2032.)

So if you want to prepare for the "end days," you can start by gifting me your truck today. Otherwise, back away from the television and critically evaluate your sources of information. (Hint: Fox "news" is the leading source of misinformation.) The end of this world has already been scheduled to occur in 6 billion years, give or take, when the Sun runs out of helium. It's probably not something worth worrying about during your lifetime.

It's always a little deflating to me when otherwise intelligent people confuse coincidence for revelation (apophenia), conflate superstition and religion (fundamentalism), or constantly pass off myth as fact (stupidity). Still, it's hard for some of us to pass up an opportunity for mischief.

A while back, when the Mayan calendar end-of-times foible was making the rounds, one couple in our neighborhood started preparing for the end. I so wanted to ask for the keys to their new but soon-to-be-unneeded truck, but I resisted temptation in the end. They're still of this earth, and I'm still making payments on our old truck.

Lunar eclipse cycles are explained in relatively easy (here), hard (here) and challenging (here) terms.

"Apophenia" helps explain delusional behavior and conspiracy theories.

Wednesday's early-morning lunar eclipse punching through cloud layers in western Montana