As the moon moves between Earth and the sun, a lunar shadow will be cast along a hundred-mile-wide (160-kilometer-wide) path, traveling virtually the entire length of the southern Pacific Ocean over several hours and making landfall early Wednesday in Australia (Tuesday afternoon in the United States). (See "ring of fire" eclipse pictures.)

"The best places on land to see totality"—when the sun appears to be completely blotted out by the moon—"is along 62 miles [100 kilometers] of coastline on northeast Australia, overlooking the Great Barrier Reef and the Coral Sea," said eclipse expert and National Geographic Society grantee Jay Pasachoff, an astronomer at Williams College in Massachusetts.

"Anywhere to the east, one has to be on a ship