A Most Unusual Observation Point

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View Photos Live From the Easter Island Eclipse >>

Easter Island Eclipse” will air on Sunday, July 11 at 11P et, which may be the most extensive coverage of a celestial phenomenon in the history of television. The program will include video shot that afternoon of a total solar eclipse visible from Easter Island in the South Pacific, and then quickly edited for telecast. The images will provide a view of a total solar eclipse far more detailed and realistic than TV viewers have ever before seen, thanks to the powerful, advanced solar telescopes, created by designer Andrew Lunt, through which the documentary crew will shoot sophisticated high-definition video.

It’s an odd twist of fate that the best place to observe the upcoming eclipse turns out to be a remote island, best known for the giant stone figures implanted on its hillsides sometime between eight and 12 centuries ago. But maybe it’s only fitting. Rapa Nui, as it is called in the local vernacular, has itself been a subject of fascination to the outside world since Easter Day 1722, when three ships owned by the Dutch East India Company spotted a tiny speck on the horizon and decided to claim it for their employer, as Europeans assumed was their right in those days. Dutch captain Jacob Roggeveen and his sailors rowed ashore in hopes of finding fresh water and supplies, only to be startled by their discovery’s almost ethereal strangeness. It was a barren, windswept land, with what had looked like sand dunes but turned out to be hills of brown, sun-scorched grass. They were soon greeted by the Easter Islanders, themselves descendants of Polynesian explorers who had reached the island sometime during the Middle Ages in Europe. With their extensive tattoos and earlobes stretched out by heavy piercings, the islanders’ appearance was startling to the Dutch, but not nearly so much as what they found as they wandered about the island: Nearly 900 giant volcanic stone faces, each roughly 13 feet tall and 14 tons, that early inhabitants of the island had carved and hauled to various ceremonial locations around the island, as homages to the ancestors that they regarded as minor gods.

English Captain James Cook, who visited Easter Island 52 years later, was puzzled by how its sparse, undernourished population — which he observed subsisted largely on potatoes, yams, birds’ eggs and occasional catches of fish — could have carved and hauled into place the “stupendous stone statues” that he saw. As he noted in his journal,

They have no other tools than what are made of Stone, Bone, Shells & etc.

What Cook didn’t know was that the barren island had once been verdant and lush, with forests of giant palms, and that the Polynesian colonists had established an agricultural civilization prosperous enough to support several thousand inhabitants. Easter Island society had done so well, in fact, that inhabitants had been able to allocate a sizable portion of the labor force to building the giant stone monuments. But then, the society imploded, due to an environmental catastrophe whose explanation is still not fully explained. While some have suspected that the islanders cut down too much of the island’s forests, in a 2007 Smithsonian article, University of Hawaii archaeologist Terry Hunt advances a more bizarre scenario — that rats, brought from Polynesia via boat either as stowaways or as a meat source, destroyed the forests.

However they got to Easter Island, the rodents found an unlimited food supply in the lush palm trees, believes Hunt, who bases this assertion on an abundance of rat-gnawed palm seeds. Under these conditions, he says, “Rats would reach a population of a few million within a couple of years.” From there, time would take its toll. “Rats would have an initial impact, eating all of the seeds. With no new regeneration, as the trees die, deforestation can proceed slowly,” he says, adding that people cutting down trees and burning them would have only added to the process. Eventually, the degeneration of trees, according to his theory, led to the downfall of the rats and eventually of the humans. The demise of the island, says Hunt, “was a synergy of impacts. But I think it is more rat than we think.”

In the island’s aboriginal cosmology, their terrestrial realm, or kainga, served as a separation between the sky world of light and the darkness of the underworld. For scientists interested in observing the total eclipse, however, Easter Island has a different distinction, which it owes to the nuances of the shadows cast by the eclipse:

Well it seems natural that during the time of the eclipse anyone standing on the side of the earth facing the sun should be able to see the eclipse. But that’s not how it works. There are actually two shadows that the moon casts upon the earth. This first one is very large and very diffuse, thousands of miles in size is the penumbral shadow. Inside of the penumbral shadow an observer can only expect to see a partial eclipse of the sun, the moon doesn’t completely block out the sun. But here in this much smaller, much darker shadow, the umbral shadow, no more than a couple of hundred miles in size the moon completely blocks out the sun, and here you can expect to see a total eclipse.

The trajectory of the umbra’s shadow is known as the path of totality, and it will begin just south of the South Pacific isle of Tonga then race easterly for a few short minutes at a speed of about 1,000 miles per hour. It will cover a fraction of one percent of the Earth’s surface, and most of the area covered will be water. The one prominent spot of land inside the shadow, as it happens, will be Easter Island.

Video: A total solar eclipse occurs only once every 18 months; allowing scientists to investigate the sun in a whole new light.

Don’t miss “Easter Island Eclipse” on Sunday July 11 at 11P et and again on Thursday July 15 at 10P et/pt.

Also, check back on the Inside NGC blog Sunday night for pictures from the moment at the site!