But he drifted easily across the Pacific Ocean, carried by a freak weather pattern that still baffles scientists 500 years later: El Nino.

So says a new paper co-authored by Scott Fitzpatrick, assistant professor of sociology and anthropology at N.C. State University.

Seeking a western route to the riches of the Spice Islands, Magellan navigated the narrow straits at the tip of South America that now bear his name.

He should have nosed out into the Pacific and been hammered toward Chile by winds too strong for his 16th century ship to buck. English explorer Sir Francis Drake took just such a buffeting not many years after, on his own Pacific journey.

"It's just notorious for being stormy," Fitzpatrick said Thursday. "But when Magellan gets around there, it's extremely calm. They just cruised right up there. That's how the Pacific got its name."

As far as Fitzpatrick knows, he and Richard Callaghan, a geographer with the University of Calgary, are the only researchers to examine the role of weather in the explorer's epic journey.

Magellan's trip is so soaked with drama, he said, that historians tend to overlook the slow cruise across calm seas.

Though Portuguese, Magellan sailed under the Spanish flag, convincing boy-king Charles I that the Spice Islands in modern-day Indonesia were Spanish territory and ripe for plunder.

He sailed with five ships in 1520, losing two of them before he even reached the Straits of Magellan, and by some accounts, having a band of mutineers drawn, quartered and impaled on a South American beach.

Once he reached some Pacific islands, the voyage is just as ripe with lore. Tropical orgies. Starvation so severe the men ate bread crumbs soaked with rats' urine, then the rats themselves.

To bolster their theory, the two researchers used 50 years of modern ocean and wind data compiled by the U.S. Navy and Coast Guard. Though Magellan's trip precedes that data by four centuries, they believe the numbers form patterns that hold up over time.

When Fitzpatrick and Callaghan looked at the data for the southern tip of Chile, it showed Magellan's craft should have been mercilessly battered against the coast.

Only the weakened winds associated with El Nino -- first described in the early 20th century -- would have allowed quick passage.

In a cruel twist, the same lucky weather also doomed the Portuguese mariner, both researchers believe.

Starvation had severely gripped Magellan's crew as they crossed the Pacific. But rather than head for the Spice Islands, which are near the equator, Magellan sailed north to Guam.

The only explanation that survives from crewmen is that Magellan suspected the Spice Islands would have scant food. In El Nino conditions, droughts are common in the South Pacific.

Once farther north, Magellan got in a skirmish between island chieftains in the Philippines. He befriended one and attacked another, fighting more than 1,000 natives with roughly 50 men, all clad in heavy armor and clanking about in the water.

Hacked, run through with spears, Magellan died in the Philippines before his voyage was finished. Of more than 200 men, only 18 returned to Spain.

A condensed version of the research paper appears in the journal Science today.

It is ironic, Fitzpatrick said, that Magellan would find a small sliver of meteorological fortune amid all the catastrophe his voyage endured, then perish by that same sliver.

Somewhere, Magellan's remains, which were never recovered, commingle with the sand and sea through centuries of fickle weather.