When the Sun Disappears and Dolphins Do Back Flips
During total eclipses of the sun, at least one ancient culture performed mass human sacrifice to placate the gods. While our understanding of these celestial phenomena has grown, the author rediscovers the scientific curiosity they engender.
Since death and taxes are the only sure things in this life, it falls to the individual to come up with a compelling To Do list to fill the brief measure of time between cradle and grave. The list may include such obvious entries as: find a lifelong companion, get a good career, and change the oil every 3,000 miles. A less obvious entry, but one that belongs very high up, should be: witness a total solar eclipse, such as the one that will sweep over the Caribbean for a respectable four minutes on February 26, 1998. In 1991, I stood under the shadow of the moon for almost seven minutes, aboard a ship in Mexico’s Sea of Cortez. You want this kind of experience. Trust me.
Although eclipses helped confirm Einstein’s theory of relativity, scientists no longer rely on them for much new knowledge. Satellites can get most solar data better and faster than can eclipse expeditions, which scientists had to organize to obtain such information during the early part of this century. What eclipses still can do, however, is fill us with the kind of wonder that sparks a scientific interest in the first place. Besides, it’s a hell of a show.
On July 8, 1991, having made arrangements a year or so in advance, about 1,300 professional and amateur astronomers boarded the cruise ship Viking Serenade in Los Angeles. We set sail for the sliver of sea between the Baja Peninsula and the rest of Mexico, one of the prime locations for the solar eclipse that would be visible, weather permitting, three days later in a narrow band stretching from Hawaii to Brazil. We did this despite the comments of one Jess Arais, who told the New York Times he planned to watch the eclipse on television from the comfort of his home in San Jos Viego, Mexico. “It’s a little crazy for the gringos to come so far to sweat,” Arais said. “They have much better televisions than we do.”
Nevertheless, we wanted to see for ourselves what people have always fussed about whenever the moon gets between the earth and the sun. “Most ancient peoples were alarmed by the occurrence of an eclipse,” E. C. Krupp, the director of Los Angeles’s Griffith Observatory, told us on the Serenade. “They were anxious about what the eclipse might mean.”
“Eclipse” is a Greek word, its root meaning omission or abandonment. People certainly used to behave during eclipses as if they were being abandoned by their gods. Krupp, who researched the subject for his book Echoes of the Ancient Skies, described the reaction-as recorded by sixteenth-century Aztecs-to an eclipse visible from Mexico. There was “a tumult and disorder, all were disquieted, unnerved, frightened. There was a weeping. The common folk raised a cry lifting their voices, making a great din, calling out, shrieking,” while in the temples chants were sung. Furthermore, “people with light complexion were slain. All offered their blood.” A warning was given that “if the eclipse of the sun is complete, it will be dark forever. The demons of darkness will come down, they will eat men.”
I would discover that eclipse watching still induces a frisson of fear. I blame some evolutionarily grounded hard-wiring that bypassed my scientifically informed brain and told my body that something highly unusual and maybe even dangerous was going on. Eyewitness accounts of animal behavior during eclipses describe other creatures, too, as seeming upset. These astronomical events have probably been creating havoc for millions of years.
The crush of amateur astronomers would cause the only obvious havoc aboard the Serenade. One person wore a T-shirt showing the locations and total amount of time he had spent under the eclipsed sun. Another looked a great deal like the TV character Gomez Addams, probably because he was actually actor John Astin, a passionate amateur astronomer. (I first spotted him during a lifeboat drill. The possibility of sharing such a craft with the sire of the “Addams Family” affirmed my belief that this could be an interesting trip.) Our little voyage would be less emotionally taxing than the experience of our ancestors. We foresaw little chance of ritualistic mass murder. And where scientists seeking to confirm the theory of relativity had to endure grueling expeditions-such as delineating a safe route among enemy countries during World War I, or trekking 100 miles to an Australian site using camels to carry dismantled telescopes-on our trip we had only to come to grips with a lifestyle that could be a bit, well, loopy.
For one thing, preparation for observing the eclipse-on a ship designed for indulging vacation fantasies toward the end of the twentieth century-seemed to take a back seat to seeing how much we could eat. Cruises, I learned, commonly engage in this form of subtle torture. Buffets started at dawn and continued past midnight, in addition to regular meals and room service. (Any passenger on an eclipse cruise should bring two safety items: a solar filter for viewing the partial eclipse, and really big pants.)
Our trip’s organizers had arranged for numerous scientific seminars. Still, an unusual ambience also tinged these, for the rooms in which the talks took place ordinarily hosted lounge singers and bingo games. The names of the nightclubs, in keeping with their true identities, give an idea of the cognitive dissonance and kinds of upholstery to which passengers were subjected. One could listen to the presentation “The Corona of the Sun and X-Ray Astronomy” in the Hello Dolly Lounge or “Very Long Baseline Interferometry” in the Ada Dining Room.
The scientific talks did not waste much time describing the simple physics of eclipses, which are downright banal. Three bodies moving relative to one another more or less in a plane occasionally line up. Big deal.
We did learn, however, that some critical relationships make a complete eclipse striking to the mind as well as the eye. Consider the relative sizes and distances of the entities involved. If the earth were 2 inches wide, the moon would be a shade over 0.5 inch across and 5 feet away. Meanwhile, the sun would bulk in with an 18-foot diameter and would stand two-fifths of a mile distant. Both sun and moon happen to occupy about one-half of one degree of sky, the moon being just about 400 times closer to us than the sun, but the sun having around 400 times the diameter of the moon, a coincidence of cosmic significance to eclipse watchers.
That’s not all that counts, either. Since we are in an elliptical orbit around the sun, and the moon is in an elliptical orbit around us, the bodies are not always the same distance from us, which means their apparent sizes vary slightly at different times. If the moon is far enough from us while the sun is at a close point in our orbit, the moon can be too small to block the entire sun.
Fortunately, our situation was the exact opposite. The moon would be almost as close as it gets (just a few hours past perigee, its closest point to us). The sun, on the other hand, would be almost as far away as it gets (with the earth being only five days past aphelion, the point in our elliptical orbit when we are at our greatest distance from the sun). Thus we would not only be certain to experience totality, but the relatively large apparent size of the moon would block the relatively small apparent size of the sun for an exceptionally long period-about seven minutes, depending on where one stood on the earth. Not until June 13, 2132, will the heavens grant a longer total solar eclipse.
We were primed. Then, the day before showtime, the equivalent of a sprained ankle before a marathon threatened us: clouds. An eclipse on an overcast day is like watching Star Wars when the curtain is down. Swaths of blue sky that afternoon eased the tension.
Still, the possibility prompted the passengers to talk softly-do people equate loudness with jinxing?-about what complications might ensue. “The weather has ever been the despotic rule over the fates of eclipse expeditions,” wrote Isable Lewis in the U.S. Naval Observatory’s 1924 Handbook of Solar Eclipses. Indeed, at dawn on the big day our direction-now past the tip of the Baja, we were heading northeasterly-found us traveling toward a block of cirrus clouds. But being at sea gave us a trump card: we could travel elsewhere. By contrast, clouds would shut out many people who had traveled to a stationary position in Hawaii.
In fact, part of our saving grace turned out to be someone who came from Hawaii, specifically its state university-James C. Sadler, a professor of meteorology. Consulting satellite photographs of the area that were faxed onboard, he convinced the scientific overseers of the trip that “the only thing to do was turn back toward the northwest,” recalls Joseph Chamberlain, then president and director of Chicago’s Adler Planetarium (now president emeritus). Still, “the ship was only going 6 knots, and we knew the clouds were catching up with us. We increased the ship’s speed another 6 knots” and the clouds fell back. The nearly 2,000 passengers and crew took up positions on the uppermost decks amid the brilliant colors of sun-glorified sky and sea.
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