The Longitude Problem

How do you lose an island? Perhaps when it was never there in the first place! Scientists from the University of Sydney went looking for ‘Sandy Island’ in the South Pacific, only to discover that it doesn’t exist.

Although a large piece of land sitting between Australia and New Caledonia in the South Pacific is marked on many world maps and weather and marine charts, on closer inspection it turned out there was nothing to be found. Dr Maria Seton, who was part of the crew on the Southern Surveyor, says "we became suspicious when the navigation charts used by the ship showed a depth of 1400 metres in an area where our scientific maps and Google Earth showed the existence of a large island."

The history of cartography - the making of maps - is full of mistakes. Incorrect calculations and even uninformed guesses have resulted in entire landmasses being missed out or drawn with very odd-looking proportions. Perhaps the most famous example is that of Christopher Columbus landing in the Americas, having set out for south-east Asia entirely unaware that an undiscovered continent lay to the west of Europe.

As yet, it is not clear why Sandy Island has appeared on so many maps, but as Nabil Naghdy, Google Maps product manager for Australia and New Zealand notes, "the world is a constantly changing place, and keeping on top of these changes is a never-ending endeavour."

Watch the Twig films below to learn more about how cartographers and sailors have tried to master the art of marine navigation. Has modern technology helped us to better understand the hazards beyond our coastlines?