It was very early on a beautiful July morning in Hawaii, and as I looked to the west onto the vast Pacific Ocean, I saw it coming. A wall of darkness was racing towards me at over 5,000 miles an hour.
At 7:28:09 am, the Big Island of Hawaii was plunged into darkness and thousands of people who had traveled half way around the world to witness this spectacular event were deprived of seeing it happen. A stubborn layer of cirrus clouds had formed over the island at 9,000 feet making it impossible to see the most impressive eclipse of the sun to occur until the year 2132.
I was one of the blessed ones. I had a front row seat along with 220 Astronomers who had assembled atop Mauna Kea at 13,796 feet above sea level. The sky from my vantage point had become an eerie twilight reminiscent of a bright moonlit night.
I looked directly at the sun, or at least where the sun should have been. It wasn't there. In its place a black hole precisely the size of the sun had been neatly cut out of the sky. The pearly white corona danced around the black hole and added to this unnatural setting were stars plainly visible in the sky.
There is no amount of knowledge or "civilizing" that quite prepares you for the primeval reaction that stirs within you. Like the Grand Canyon, Victoria Falls or the first day of Spring, the totality of a solar eclipse must be experienced first hand to be truly appreciated. No photograph or video camera can do it justice.
It lasted four minutes and 10 seconds and then a bright burst of sunlight exploded from the top of the black disc. As the Corona was extinguished, for a brief moment a gigantic diamond ring hung in the heavens. It was daylight once more, the sunlight seemed to twinkle for a time and the wall of darkness could be seen in the east racing toward a noon-time rendezvous in Mexico.
There are many factors that affect the characteristic of a total eclipse viewed from earth. Planets throughout the universe experience an eclipse when their moons pass in front of their sun. How many planets have a sun and a moon with an angular diameter so nearly the same? Both our moon and our sun occupy 1/2 degree of arc as viewed from the earth. Their precise angular diameter varies slightly depending upon the relative position of the earth and moon in their orbits. The longest solar eclipses occur in early July, when the earth is near aphelion and the sun's disk appears smaller.
The moon is too far away from the earth most of the time to completely cover the sun and therefore the moon must be near perihelion in its orbit to produce a total eclipse. The lunar orbit is tilted 50 with respect to the sun's apparent movement through the sky. This means that an eclipse can occur only at the two occasions in the moon's orbit where the path of the sun is crossed. Each time the moon completes an orbit around the earth it crosses 1.60 west of its previous crossing. A new moon must then occur at this crossing to produce a total eclipse. The total eclipse is only visible in a narrow path along the earth's surface. The longest eclipses occur at lower latitudes because the portion of the earth directly under the moon is closer to the moon and penetrates several thousand miles farther into the moon's shadow.
A total eclipse is of great value to the scientific community. In 1868, the element Helium was discovered during a spectroscopic study of the eclipsed sun. Helium was not identified on earth until 1895. On May 29, 1919, the bending of starlight passing near the gravity of the eclipsed sun provided the first actual confirmation of Einstein's General Theory of Relativity.
The moon acts like a gigantic notch filter that precisely removes the "fundamental" of the sun's energy. The full dynamic range of astronomical equipment can then be used to study the eclipse without being overloaded by the sun's presence. For years, scientists have carried equipment to remote locations in the desert or the jungle hoping to study the phenomena. All too often these "remotes" were plagued by Murphy. The eclipse on July 11, 1991 in Hawaii was different.
For the first time in history the center of the eclipse passed within 1.5 miles of the largest complex of astronomical observatories on earth. The summit of Mauna Kea is the site of nearly a dozen optical and infra-red telescopes operated by the University of Hawaii, Cal-tech, NASA, Canada, France and the United Kingdom.
Two factors did detract from the ideal conditions. The cirrus cloud layer below us reflected some light from outside the eclipsed region resulting in an eerie twilight effect, and the Mt. Pinatubo eruptions half a world away in the Philippines had deposited a layer of volcanic ash in the upper atmosphere.
I had planned for months to travel from Indiana to visit the Big Island during the eclipse. I knew the summit would be off limits. Only scientists, astronomers and a few other blessed souls would be allowed up there. But just days before I arrived I received word that a two man television crew would be permitted on the summit to provide a pool video feed. Telephone company fiber optics would carry the signal from the summit to a KU Uplink located down on the beach. Twenty nations were expected to carry the feed.
It turned out that the two man crew would be supplied by KWHE-TV14 in Honolulu. As LeSEA Corporate Director of Engineering for KWHE-TV, I volunteered my services.
The night before the eclipse we slept in sleeping bags at the Hale Pohaku Astronomer's Quarters located at the 9000' level. We arose before dawn and traveled up to the frigid high altitude of the summit to set up the remote. The smallest physical tasks were exhausting and after a few hours at 13,796 feet, the mind slows to 300 baud. But despite that, the vivid spectacle of one of nature's greatest events will remain etched in my memory for the rest of my life.
-Douglas W. Garlinger
July 11, 1991