Until people learned that solar eclipses are caused by the moon blocking the sun, they were scary events. Even today, eclipses are cloaked in superstition and ritual by some cultures.

For more than a century, scientists have traveled thousands of miles to study solar eclipses. The eclipse of 1919 became especially famous after a British scientific expedition observed it from the island of Principe off Africa's west coast.

The expedition's scientists claimed that the darkened sky revealed a slight bending of light from stars near the eclipsed sun. Newspapers around the world announced their discovery, which confirmed Albert Einstein's theory of relativity. Though the eclipse measurements were controversial, Einstein became an instant scientific celebrity.

Some eclipse expeditions never obtained the photos and data that had been carefully planned years in advance. Instead, clouds blocked their view of the eclipse. Amateur eclipse chasers also have been subjected to the vagaries of clouds.

In 1991, my wife, Minnie, and I went on a cruise to see our first total eclipse.

The ship cruised south under dense clouds for two days until reaching the point of maximum eclipse off Baja, California. Fortunately, a highly experienced Pacific weather forecaster was on the cruise, and his expertise allowed the ship's captain to guide us to a large hole in the clouds just in time for an unforgettable view of the eclipse.

During that eclipse I measured waves in the ozone layer caused by the cooling effect of the darkened sun.

This finding became a paper in a scientific journal, and I hoped to repeat the measurements during the 1994 annular eclipse that would cross over North Texas.

When I arrived in Lubbock the day before the eclipse, the sky was totally overcast. I drove to the National Weather Service office, where the forecasters were intrigued by the measurements I planned. They took me back to their computers and did a quick weather forecast for the next day. Their advice was to head for Las Cruces, N.M., which I promptly did.

The eclipse was perfectly visible the next morning, and the ozone measurements confirmed that eclipses do indeed produce waves in the ozone layer.

On May 17, Minnie and I drove to Albuquerque to see the recent annular eclipse. The sun would be too low in the sky for ozone measurements, so this time my goal was to make pinhole photos of the spectacle.

The sky was nearly clear, but a layer of clouds over the west horizon threatened to block the eclipse. While I was making plans to drive south, the clouds began to dissipate.

We had a perfect view of that "ring of fire" eclipse.

