Monday, May 21, 2012


"There is no veil between me and the wheel of fire. I begin to see it even with my waking eyes, and all else fades." - Frodo Baggins
In the last week, Sunday's solar eclipse running through California (and some other western states) started making the papers, but I'd had it in my calendar for a long time. (It's runner-up in longevity there to the total eclipse scheduled to cross the US from Oregon to South Carolina on August 21, 2017.) I bought eclipse glasses in advance and made a simple pinhole posterboard viewer.

Obscuration, as it's impressively called, was to be 83.5% at home, dramatic enough, and as this was only an annular eclipse - only an annular eclipse, as if that wasn't a big deal - it went no higher than about 87.9% anywhere. Nevertheless it seemed worth the trouble to travel a few hours north to see the full solar ring. Checking web sites of newspapers for conveniently-located towns in the annular zone revealed that there'd be stuff going on at the Sundial Bridge, a monumentally-sized footbridge across a small reservoir in Redding. So thither my brother, temporarily posted in Sacramento, and I went. As we drove in mid-afternoon, we anxiously scanned the sky for the increasing clouds accurately predicted by the weather service. But they never got heavy enough to be a problem, fortunately.

Performing one's eclipse-watching among a couple hundred other maniacs proved superior to being off by ourselves somewhere. For one thing, there was the camaraderie and comfort of knowing that if we were going to look silly staring at the sun in goofy-looking cardboard glasses, at least we were doing it in a lot of company.* For another, some of those folks had superior equipment. Not all of them: one person had cut an 11-inch wide hole in a foot-square piece of cardboard. This didn't focus enough light to produce anything in its shadow, and she was reduced to simulating the eclipse by passing another piece of cardboard in front of it.

Best of all was the man with a telescope which displayed a crisp blazing-red image in its eyepiece; I was looking at this at the moment the ring broke and could see the solar flares protruding from the surface; intensely neat. Teenage volunteers from the adjacent natural history museum had set up white cardboard on easels and were focusing the shadow image through binoculars on them. This was quite effective and towards the climax of the event it looked like this:

But you didn't even need that much. A remarkable property of the sun under eclipse is that the shape of its obscuration will show up in any tightly curved shadow, even if it's not circular. The image in my posterboard viewer was small but clear. (And I left one at home with B., who also got good use out of it.) A number of bloggers I read have taken pictures of the eclipse as seen in the shadows of tree leaves. The easiest and quickest form of eclipse viewer is to cross two slightly spread fingers over the same fingers of the other hand. The square hole formed is good enough to cast the visible shadow of a partial eclipse.

When we arrived, an hour before showtime, a long line of people stretched out from the museum gift shop. These turned out to be the people who had not planned ahead and failed to have bought eclipse glasses. The glasses ran out before the line did, and extra ones were popular for a while, demonstrating the power of an exploitationist capitalist system based on an economy of scarcity.

The moon hit the sun's edge at 5:11 PM. Anxiety over the clouds was intense. The growing bite out of the sun was charted in our various viewing methods. The sun gradually became a crescent sliver, as an eerie semi-twilight descended over the setting. The full ring of the sun formed on schedule at 6:26. It was so thin that the two-finger method and my pinhole viewer no longer worked. Thoughts of the fiery One Ring of Sauron were inevitable. In the telescope, the moon, previously invisible, glowed a faint white with the sliver of the sun all around it. As you watched, you could actually see the ring getting thicker on one side and thinner on the other in real time. Four and a half minutes afterwards, the ring broke through.

We all breathed a sigh of relief. We had seen the eclipse, and the sun was returning. Another hour of watching the shadow slowly diminishing awaited true devotees, but the rest of us had already seen that show in reverse, and it was time for dinner. One traffic jam of a mass exodus of cars from the museum parking lot later, we were off to feed at the Black Bear Diner, and then back to Sacramento after sunset, having enjoyed our enrichingly astronomical day.

*Including a small cadre of acquaintances of mine who'd come up from Oakland.

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