Scientists and star-gazers from around the world began priming their telescopes in Brazil Wednesday for a total eclipse of the sun that will cast its shadow across a thin swathe of South America Thursday.
The total eclipse, caused by the moon passing in front of the sun, will appear over the Pacific Ocean and then rake a 125-mile-wide shadow across Peru, Bolivia, Paraguay and southern Brazil before disappearing in the Atlantic."What is unusual about this eclipse is that it will be a total blackout right on top of some of the best infrastructure available to observe it in Brazil," said Sayd Jose Codina Landaberry, director of Brazil's National Observatory.
Crowds of new-age travelers are expected to gather at Machu Picchu, the mountaintop city of the Incas in Peru, to view the eclipse.
In Bolivia, the tourist board has reportedly accused Peru of lying about the superior quality of the blackout in that country to lure foreign visitors.
Hotels in southern Brazil report a near sell-out as tourists book their places for the event which is due to last two hours and 38 minutes - but only four minutes of which will count as a total eclipse.
In Foz de Iguacu, close to the spectacular waterfalls that mark the frontiers of Brazil, Paraguay and Argentina, botanists and biologists will observe how plants and wild animals such as jaguars, raccoons and monkeys react to the unexpected nightfall.
Around a hundred star-gazers have gathered in Criciuma, a beachside town in the southern state of Santa Catarina. They are hoping for a momentary glimpse of the sun's corona, or the halo of light that should appear around the black form of the moon.
Normally invisible in the sun's glare, the corona is a vast sphere of constantly mutating gas surrounding the sun, the outer reaches of which interact with the Earth's own stratosphere.
"There's still a lot we don't know about the corona," Landaberry said.