Standing under the shadow of the Moon: Thoughts on totality

SYFY WIRE Bad Astronomy

Standing under the shadow of the Moon: Thoughts on totality

By Phil Plait

On August 21, 2017, I experienced something I have never in my life seen before: a total eclipse of the Sun.

I haven’t had much chance to write about it in the time since it happened; I was on travel to see it, and pretty busy. But I’ve had some time now, and I have thoughts.

Yesterday, I posted some lovely photos and videos from the eclipse. As an aside, I tweeted about the post, and the replies it’s getting are loaded with more imagery and videos, too (as well as a followup tweet I posted).

I did not take any photos during totality, because I knew people along the path of totality would take zillions of photos that would reflect my own view. But the real reason is that not worrying over taking photos meant I was free to experience the eclipse. I still had much to do in those two minutes and nine seconds — I had a group of about 30 people with me as part of Science Getaways, a science vacation company my wife and I run. We were at a guest ranch near Dubois, Wyoming, and I had enough on my mind without fretting over getting good pictures!

Mind you, after a lifetime of astronomy, 5+ decades of looking up at the sky whenever I get a chance, this was my very first total solar eclipse. Oh, I’ve seen plenty of partial ones from various locations, but the difference between partial and total is, well, night and day.

And now that I’ve, myself, stood under totality, I find it revelatory to find that the moments leading up to it were just as exciting as the eclipse itself! Of course, we were all excited — all of us were science enthusiasts at the least, and for nearly everyone there this was their first time — but there was more to it than that.

The first thing we all noticed was the air cooling, sometime after the Sun was 50% covered. Wyoming is dry, and the air cools immediately when the Sun is blocked (either by clouds, as it’s setting, or — duh — during an eclipse). Then, some minutes later, the light became … odd. The Sun is a disk in the sky, and this blurs shadows a little bit. But as more of it becomes covered, the shadows become sharper, and the light changes timbre (to mix a wave metaphor). It almost felt like being lit by a fluorescent light, where the quality is different, colder.

Then, the sky started to darken toward the west, and we could see the Moon’s shadow rising in the sky. Venus started becoming more obvious and, looking back at the Sun (properly equipped with glasses, of course), the last thin crescent of the Sun was evaporating. I heard people exclaiming and laughing. As we watched, the crescent tips approached each other, the arc of Sun vanished, and suddenly, we saw it. Totality.

It was beautiful, stunning, unearthly. I’ve never seen anything like it. The Sun’s corona, visible to the naked eye! Venus shone brilliantly, as did Jupiter. Other stars were apparent, but honestly I don’t remember those so much. I was enthralled by the Sun’s atmosphere itself.

And then, almost as soon as it began, it was over. I had a timer running, and at two minutes I told everyone to look away and put their glasses back on. Seconds later, boom. The Sun’s surface peeked out from behind the other side of the Moon, and the events of the past 90 minutes played themselves out in reverse. We all agreed those were the fastest two minutes of our lives.

Talking about our shared experience with a friend after, a thought struck me: A big part of what makes an eclipse so amazing is the event’s timing. If the Moon suddenly blocked the Sun with no prelude at all, it would be incredible, certainly. But the hour or more of tension leading up to it, the change in the sky, the temperature, the environment around us ... it takes just the right amount of time to ramp up our human emotions, to send that thrill through our minds and bodies that primes us perfectly for the main event.

Anticipation builds suspense, and suspense leads to immense satisfaction if the payoff is solid. In an eclipse, that payoff is gold.

As I talked to my friend about it, I had to chuckle. Creationists like to point out that we’re the only planet that can get a total eclipse, a claim that (like most of what they say) is wrong. Other planets see them, too, and even some moons see other moons eclipse the Sun. Sometimes the creationists claim that, if the Moon were any closer or farther, we wouldn’t get the glory of the corona, or see solar surface features. This, too, is wrong; the Moon’s orbit is elliptical, and it changes its distance from us by about 10%, so sometimes we get more or less of an eclipse. None of this implies any kind of design, other than the coincidence of orbital mechanics and evolution having us humans here on Earth at this time.

But my amusement when thinking on this was because of that prelude. A total eclipse that lasted two hours would get somewhat dull, and one that had no preamble would be so sudden that our emotional reaction might be more muted. But that half hour or more of changes around us was the near-perfect amount to thrill us, to get the anticipatory juices flowing. If creationists had any claim at all to design, it would be that timing, almost heaven-sent to be tuned to our human senses.

Don’t get me wrong. I take no stock in claims of design, other than those that emerge from the non-sentient properties of physics and biology. What looks like design is just the outcome of generally simple rules that play out given enough time.

But that lessens the experience not at all and, in my opinion, magnifies it. We humans are capable of appreciating beauty, and this adds a profound depth and dimension to our experiences. Knowing the science does this as well.

I can explain with great precision the science behind the eclipse, including the roles of orbital mechanics, trigonometry, geometry, refraction, magnetism, and chemistry. I have heard arguments that this lessens the awe, somehow detracts from the experience. The people making this claim feel that understanding something subtracts from that thing.

This is nonsense. Knowing more adds to the experience. It gives you an appreciation of how this event is unfolding, why it happens, and provides tangible insight into how rare and precious a total solar eclipse is.

I felt no muting of the thrill as totality approached, no cold logic pushing out the awe and wonder. People around me cried out, laughed, yelled, and even wept as the Sun’s crown emerged from the darkness, and I was right there joining in with them. It was a deeply emotional experience, amplified and refined by the knowledge of the cosmic processes that forged it.

Art and science are inseparable; to fully appreciate one, you must have at least some sense of the other. An eclipse is an opportunity to have both trumpeted from the heavens itself. It’s an extraordinarily beautiful Universe, and I’m grateful to have the chance to stand in scientific reverence before it.