(CNN) -- "Extraordinary claims require extraordinary evidence," the astronomer Carl Sagan once said. In the case of the extraordinary claim concerning the possible discovery of the wreck of Santa Maria, the flagship of Columbus' fleet, it's clear that we aren't there yet. In fact, we seem to be getting further away from proof all the time. The potential discovery of the wreck, which happened on the first of Columbus' four voyages to the Americas, has become a flashpoint for the difficulties of determining the authenticity of artifacts honored in memory but difficult to locate in the present. The discoverer, underwater explorer Barry Clifford, says he has quite a few reasons to believe he's found the right ship in the Caribbean Sea. Columbus left details in his diary about the location of the sinking, which happened near Haiti on Christmas Day in 1492. Clifford maintains that description matches the shipwreck's whereabouts.
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Explorer says he found wreck of Santa Maria, flagship of Columbus' fleet, off Haiti
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Laurence Bergreen believes discovery is highly unlikely, given erosion, shifts, tides
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Bergreen:The wooden parts of the ship probably have not survived 500 years
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Bergreen: Given potential historic significance, this wreck needs careful examination
And, most frustrating of all, perhaps, @placeholder occasionally fudged his navigational records.