Thursday, May 24, 2012

Eclipse Diary, Part 3 – Ring of Fire

Deborah's attempt to photograph the eclupse (far right)
Photographing through a welding visor
The solar system is mostly empty space with leeetle teeny objects hurtling round a star (and some of them, around others) that, while quite medium and ordinary by galactic standards, is by far the largest, most massive object anywhere around. So Earth is hurtling around the Sun, the Moon is hurtling around Earth (and therefore, around the Sun in a sort of perambulatory – not a correct astronomical term, I believe – fashion). And every once in a while, the Moon comes between the Sun and the Earth, thereby blocking the sun’s rays and casting a shadow over a leeetle teensy area of Earth’s surface. Sometimes the disk of the Moon obscures the Sun – that’s a total eclipse, and in the area of the resulting shadow, there’s no sunlight, so it appears to be night – but, because the Moon isn’t always the same distance from the Earth and objects appear smaller when they are farther away, at other times, they line up but a ring of Sun remains – an annular eclipse. And because the lineup has to be exact for either of these to happen, the shadow cast by the Moon falls on only a small area of Earth. Hence, our journey to Lassen Volcanic National Park. (My husband stayed at home and got to see a partial eclipse.)

Astronomer Explains His Strategy
Once we’d established ourselves in a suitable viewing area, hoping fervently that the clouds we’d seen earlier would remain cooperatively absent, the countdown began. Solar eclipse shades are very cool things, if a bit hokey. They’re cheaply made, like glasses used for 3-D movies, but the film has to cut out all the harmful rays from the Sun in order to allow direct viewing, so everything else looks utterly black. I’ve spent my lifetime Not Looking Directly At The Sun, so at first it was odd (to say the least) to put on these black-out shades and do just that. The Sun appeared as the single luminous object in a field of black.

And then…a tiny dimple appeared in the orange disk.
Eclipse Tailgate Party
At first, I wasn’t sure I hadn’t hallucinated it. Or that it was an effect of what happens when I blink wearing my contact lenses (which ride very high on my corneas, so there’s a moment of distortion until they settle back into their proper position). But no, there it was. And a few minutes later, there it was-with-attitude. To say I’d never seen anything like it is an understatement. I’d seen movies in which eclipses were portrayed via special effects. I’d seen pictures and photos and diagrams. But this…I was seeing this with my own eyes and it was happening right now. It wasn’t in a book or a film, it was the actual real event. Instead of looking at a two-dimensional image, I was intensely aware of the vast spaces, of stars and planets and moons in their orbits, of the physics of light (what little I understand of it). The cosmos isn’t just something on a television program, it’s out there for real. Most of the time, my scope of vision (physical vision, not imagination) is so limited. This was a glimpse of how big (and how amazing) our tiny corner of the universe really is.

Pinhole Shadow Puppet (crescent "eye" is Sun)
So we watched as the nibble in the Sun grew larger. Jokes about the Cookie Monster abounded, as well as discussions about whether that was two-thirds or three-quarters. As the Moon covered more of the Sun, the quality of the light changed. Although the Sun was still quite high in the sky, it felt like twilight approaching. The temperature fell and a breeze sprang up. We speculated on how the birds would react to the full eclipse. People who did not have solar shades used various methods to observe the eclipse. The most fun of these were variations on the pinhole method (you hold up a piece of paper or similar materials with a tiny hole punched in it, and the sunlight coming through will cast an image on the surface of a screen (or sidewalk). You can also create a “pinhole” using the ventilation holes in a hat – or your hands. We made quite a lot of shadow puppets with crescent sun-images.

The Sun had become a fat crescent and then a thin one, and finally we could see the shape of the Moon as a complete circle. A hush fell over our little group as the place where the Moon had first impinged on the Sun began to glow. A complete ring appeared, and through the solar shades, both the central Moon and the surrounding sky were utterly black. People cheered and then hushed.

Using a Hat as a Pinhole Camera
The full eclipse lasted about four minutes. I spent almost all that time looking at it (as opposed to checking every few minutes during the occlusion). At one point, perhaps a minute into the fullness, it appeared to me like the One Ring from Tolkien’s The Lord of the Rings, hanging there above us all. No flaming eye made its appearance, thank goodness. The few times I lowered my shades, I noticed that even that thin ring of Sun was enough to make it day. Our shadows had doubled edges, though.

The four minutes passed all too quickly, and then the ring at the far side of where the Moon had first appeared began to thin and then to disappear, and the Sun became a thin crescent, and then a fat one. The “reveal” was much less momentous than the occlusion and seemed to go faster. I think the effect was psychological rather than astronomical, and perhaps we were all still in a state of awe from viewing the Ring of Fire.

At least, I hope I was.

2 comments:

  1. The sun darkening when it's not supposed to still has the power to overawe all life on earth .. as is ought.

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  2. We feel it in our marrow, we mammals scuttling around in the shadow of the dinosaurs... Definitely something ancient and atavistic.

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