For the first time in nearly 100 years, the shadow of a total solar eclipse is going to sweep across the United States.
The umbra — the darkest shadow cast by the moon blocking the sun — will appear in the Pacific Ocean and slice through 14 US states on Monday, August 21.
Starting around 10 a.m. PDT, parts of western Oregon will go dark in a condition called totality as the umbra travels east. The elliptical shadow will make its way to Idaho Falls by 11:33 MDT, hit Kansas City at 1 p.m. CDT, and begin to pass over Charleston, South Carolina, by about 2:45 p.m. EDT.
Although some eclipse fans spend years preparing for the event, totality lasts less than three minutes — so all it takes is one stray cloud to obscure the magic moment.
That's why some people pay thousands of dollars to fly in chartered jets and pursue the moon's shadow. In addition to beating the odds of bad weather, such hardcore "eclipse chasers" can extend their length of time in the umbra, sometimes by several minutes.
I was lucky enough to ride an eclipse-chasing flight on August 1, 2008. Here's what the experience was like.
Total solar eclipses aren't rare — they happen about once every 18 months — but most locations on Earth fall in one's path roughly once every 375 years.
Source: Amber Porter/Clemson University
That's because the umbra averages less than 100 miles wide near the equator — a fraction of a percent of Earth's dayside surface area.
However, some hardcore eclipse chasers spend thousands of dollars to chase the moon's shadow from the skies.
Totality ended after three minutes with the appearance of a second "diamond ring" on the opposite side of the moon. The eclipse phases then moved in reverse as the umbra sped eastward ahead of our jet.
After totality, two passengers — Joel Moskowitz and Craig Small — paraded a custom eclipse flag around the cabin. The two were the most devout eclipse chasers I'd ever met. "I have no intention of ever missing an eclipse for the rest of my life. I don't care where it is, even in the remotest area of the Earth," Small told me. "I have to be there, I will be there."
"When you see one, you want to see more. You get hooked," Moskowitz added. "Seeing the corona during totality is better than sex."
The trip wasn't over, though: The airplane banked hard and turned toward the North Pole. At the time, it looked like this — a bunch of fractured sea ice.
The only indication that we'd arrived at the Pole was an announcement over the intercom.
Back on the tarmac in Düsseldorf, the group snapped a celebratory photo, and then everyone began making their way home.
That evening I watched the sun set on the Rhine River and reflected on my experience. More than anything, I felt humbled.
There's nothing like an epic astronomical alignment to make you feel like you're riding a spaceship through an infinite void.
This animation shows the total solar eclipse of March 9, 2016, from the vantage of the NASA climate satellite DSCOVR.
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