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Total eclipse

September 3rd, 2017

I watched this year’s total solar eclipse from the path of totality, near Douglas, Wyoming, with my friends Tyler and Masaru. Rather than try to photograph the event, I chose to simply observe.

My 1250mm f/10 telescope with a solar filter cap gave us an up-close view as the moon slid across the disc of the sun. At first, there were no noticeable changes to the fields and hills around us, but gradually we became aware of the dimming light. Masaru mentioned how it looked like the world was underexposed by a stop or two.

I had a light meter out to track the progress of the eclipse in percentage terms. Before the eclipse started, with a very light haze from wildfires in Montana, the meter indicated 95,000 lux. At the halfway point, it read — not surprisingly — 48,000 lux. The numbers continued to drop as more of the sun was obscured. 40,000 lux. 20,000 lux. 10,000 lux. 5,000 lux. Soon, the meter indicated 1,000 lux — a 99% eclipse, about as bright as a well-lit lab bench, but still relatively normal outside. It was still impossible to look at the sun without a solar filter. The light kept dropping, 500 lux, then 100 lux — a 99.9% eclipse, and still too bright to look the sun unprotected. Between glances at the light meter, I watched the sun slip away through the telescope.

Only a small sliver of the sun’s disc remained, then just the pearls of light that are called “Bailey’s beads” (the last bits of light peeking through valleys on the moon’s surface), and then: it was gone. Totality!

I looked up at the now totally eclipsed sun. The brilliant white corona of the sun stretched satin fingers away from the now-occluded solar disc. Three red solar prominences danced away from the sun’s surface. The stars were out; the land was as dark as a full-moon night; a strange sunset circled us in the distance.

It was one of the most beautiful things I’ve ever seen. (No exaggeration; I’m getting misty-eyed just thinking about it as I write this.) The 99.9% partial eclipse and the 100% total eclipse¬†were profoundly different experiences. Totality was a million times better than even the 99.9% partial eclipse.

Total eclipse sequence (Photo: NASA/Aubrey Gemignani)

Total eclipse sequence (Photo: NASA/Aubrey Gemignani)

Two minutes and twenty seconds passed in totality. The moon moved on, and the sun popped back into view. We could no longer look skyward, so we watched daytime return to the land.

Then we sat in a 9-hour traffic jam as 500,000 people tried to drive from Wyoming back to Colorado all at the same time. Completely worth it.

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