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Sun-Earth Day Presents: Eclipse, In a Different Light


Eclipse: "When's the next one?"By Ed Hedemann

The worst thing about total solar eclipses are partial eclipses -- those partial eclipses that stay partial and never transform into totality. "Eclipse? Oh, yeah, I saw one many years ago when I was in grade school." Seen one, seen them all.

Everyone, at least over five years of age, has experienced a partial solar eclipse. Most people are not aware that a partial eclipse is happening since, at best, the sun might dim slightly, as if a cloud had passed in front of it.

Though partial and total solar eclipses are related through celestial mechanics, the experience is as different as night and day. And even more so, the vast majority of people live and die having never seen a total solar eclipse. They are unaware that they are missing what is arguably the most stunning show in nature.

I was 15 years old when I first observed a partial solar eclipse. I projected the sun's image on to cardboard using a pinhole. I also looked at it directly through high density filters. As an active amateur astronomer, I found it interesting but not THAT exciting. Looking at lunar eclipses, comets, meteor showers, the rings of Saturn, globular clusters, the moons of Jupiter was more engaging.

It wasn't until 10 years later (in 1970) that I was tempted to join a group of astronomy graduate students going from the University of Texas -- where I was in school -- to Mexico to see a total solar eclipse. This eclipse, later mentioned in Carly Simon's "You're So Vain" and observed by many people along the eastern seaboard of the U.S., was the first one that was relatively accessible to me. But still, it seemed like a very long way to go just for an eclipse. Yes, this was a total AND I had never seen one, but the partial eclipses I had seen simply didn't provide enough motivation.

Then finally, when I was 46, a really long eclipse was being touted as "the eclipse of the century," mostly because of its unusual length and accessibility to North Americans. It was 1991 and totality would last almost 7 minutes when viewed in Mexico or 4 minutes from Hawaii, where I just happened to have many relatives.

I did a lot of preparation, including scoping out the perfect site on the Big Island in Hawaii -- a desert area, up a hill to allow a good view of the approaching shadow. For three mornings before the eclipse, the weather was perfectly clear . . . until the morning of the eclipse. Heavy clouds jammed the sky during totality. Though the sun's corona was completely obscured, the eclipse wasn't a total disaster because I was able to view through the clouds two giant prominences projecting from the sun's surface. I, along with thousands of others with me in this "perfect" spot, were extremely disappointed. Nevertheless, the die had been cast: I was bound and determined to see one in a clear sky.

Three years later, day suddenly became night complete with planets, stars, and my first view of the sun's spectacular corona during a fabulous total eclipse. I was in the middle of an otherwise barren and desolate section of the 13,000-foot high Bolivian altiplano along with thousands of others from around the world. Finally, at age 50, I got to see my first unobscured totality! It was the shortest 3 minutes and 8 seconds of my life. After the cheering ended, the primary question of most observers was "When's the next one?" A question, I might add, rarely asked following a partial eclipse.

Before then, I had missed 36 total eclipses -- all but five were very inaccessible to me because of distance and cost or because I was much too young. Though total solar eclipses occur every year or two, most seem to be in the middle of an ocean, Siberia, Antarctica, or similarly remote places. I am now determined not to pass up any reasonable opportunity to see another. Life's too short. Having seen one is definitely not having seen all.


Eclipse Fact

Eclipse shadows travel at 1,100 miles per hour at the equator and up to 5,000 miles per hour near the poles.

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