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Week of 20 March 1998

Vol. I, No. 24

Feature Article

Eclipse '98

Dusk in the afternoon

by Brian Fitzgerald

Many travelers visit Aruba this time of year to enjoy the Caribbean's sunny season. But several Boston University researchers recently visited the island hoping that the sun would be obscured -- for 3 minutes and 40 seconds. That was the duration of the February 26 solar eclipse's totality, the moments in which the moon blocked the sun, casting the area into darkness.

Near-darkness would be a better description, according to Kenneth Brecher, a professor of astronomy and physics at CAS. "It was a little darker than twilight," says Brecher. "It was a peculiar light because the corona had the brightness of a full moon." In a solar eclipse, the moon blocks all but the sun's corona, or fringe, leaving a luminous ring in the sky.

Brecher saw the event not from the island, but from a cruise ship between Aruba and Curaçao, near the eclipse's center line of view. Brecher, the director of the GRS Science and Mathematics Education Center, was invited a year and a half ago by Cambridge's Sky & Telescope magazine to serve as an eclipse guide for the 2,000 people aboard the luxury liner Statendam.


The February 26 solar eclipse was caught on camera in Aruba by David Bradford, the astronomy department's systems manager.

Although the weekend before the eclipse coincided with the end of annual Carnival festivities across the Caribbean, prompting many celebrations to extend into eclipse week, those aboard the Statendam weren't exactly tourists. "Everyone was thrilled, but the reaction was surprisingly muted," says Brecher. "The passengers were all amateur and professional astronomers, including Jacques Beckers, the director of the National Solar Observatory. They had $10,000 and $20,000 telescopes."

Nonetheless, Brecher says, it was difficult to contain his excitement at seeing the peculiar atmospheric phenomenon known as shadow bands. "Shadow bands are wavy patterns on the surface of the earth that shimmer 30 seconds before totality," he says. Only a few videos have caught shadow bands clearly.

Brecher, along with BU Astronomy Professors Jules Aarons and Alan Marscher, as well as David Bradford, the astronomy department's systems manager, headed to the Caribbean to witness the western hemisphere's last conveniently visible solar eclipse of the millennium. Bradford, who went there with his wife and BU Center for Space Physics Research Associate Jody Wilson to photograph the event with a 400-millimeter lens through a focal length telescope (see photo on page 1), almost panicked when the sky became overcast right before the eclipse. "We jumped in a cab and went to the north side of the island, where there were fewer clouds," he says.

"As it turned out, the sky cleared up for the whole island," says Wilson, "and the eclipse was spectacular. I was hooting and hollering with all the locals and the vacationers."

It was Wilson's first total eclipse. That wasn't the case for Brecher, who has traveled to Hawaii and Borneo to witness these astral episodes, which have always fascinated mankind. Eclipses have appeared in mythology and literature throughout the ages, most often as symbols of obliteration and the overthrow of the natural order of things. The word eclipse comes from a Greek word meaning "abandonment." An eclipse was literally seen as the sun abandoning the earth.

The 1998 eclipse certainly brought fascination -- and fear -- to a 90-mile-wide arc in the Caribbean and South America that afternoon. In Venezuela, some pregnant women stayed indoors, fearing that the eclipse could leave skin spots on their unborn children. Some indigenous groups in the country believed that dark forces were trying to extinguish the sun, a symbol of fertility. At Venezuela's Plaza Bolivar, in the port city of Caracas, New Age devotees formed a circle, closed their eyes, and opened their palms in worship.

The darkness also brought confusion to animals in Valledupar, Colombia, where roosters crowed, night creatures stirred, and birds flew back to their nests. Accordingly, it is easy to understand why there is such an aura of mysticism surrounding an eclipse. The ancient Chinese, believing that the celestial event was a dragon devouring the sun, would bang on pots and pans to frighten away the creature.

There were no such reactions on board the Statendam, although the ship could have been called a floating asylum of astronomy aficionados. "It was like teaching an astronomy course for 10 days nonstop," laughs Brecher. "People were constantly coming up to me and explaining their theories on how the universe was formed and what black holes are. It was an interesting sociological phenomenon and a lot of fun, but it was also exhausting. If I stopped moving for 10 seconds, someone would come up to me with a question or a theory."

The Statendam was one of a half dozen ships in the area receiving continuous weather reports, just in case it had to maneuver quickly to avoid clouds. Then, 15 minutes before totality, the temperature dipped from 70 degrees to 60 degrees. "A temperature drop is normal," says Brecher. "The sun is obscured, and that itself can also cause clouds to form. But we had a perfect viewing."

Brecher says that total eclipses aren't that rare. "They happen every 18 months," he points out. "But they're often in remote places because 90 percent of the earth is unoccupied. Remember, the ocean covers 70 percent of the earth's surface."

There will be three more solar eclipses this millennium: in Sumatra and Borneo in August, and in Australia, Europe, and Asia on August 11, 1999. "Millions will be able to see the 1999 eclipse," says Brecher.

Unfortunately, the continental United States will not experience a total eclipse until 2017.