History
The story of Titanic is a well-known one, with exhaustive detail available on everything from the construction of the ship in Belfast's shipyards to the decomposing wreck at the bottom of the Atlantic.
Despite such all-consuming coverage, one major player in the disaster is often overlooked - the iceberg that sank Titanic.
Photo: An iceberg close to the site of Titanic's sinking, 15 April 1912
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Ice Engineer Claude Daley explains how icebergs change personality at sea.
Claude Daley, Ice Engineer at Memorial University in Newfoundland, has studied how icebergs change personality at sea.
The iceberg that sank Titanic met its own fate barely a fortnight after its collision with the ship.
Warmed by the water of the gulf stream, the iceberg that sank Titanic would meet its own certain fate barely a fortnight after its collision with the ship.
Once they have reached the open ocean, icebergs are pushed around by deep ocean currents.
Once they have reached the open ocean, icebergs are pushed around by deep ocean currents. It was intially steered north towards the arctic before turning toward its meeting with the world's most famous ship.
While the titanic project went full steam ahead, the iceberg that would sink it was going nowhere.
While the titanic project went full steam ahead, the iceberg that would sink it was going nowhere. It was stuck in the bottleneck at the shallow mouth of the Ilulissat fjord.
The iceberg that sank Titanic started life as a snowflake 15,000 years earlier.
The iceberg that sank Titanic started life as a snowflake 15,000 years earlier, compacting into solid ice before being broken up into bergs by melt water and the earth's inner heat.
Each iceberg is unique, moulded by its individual journey through the polar seas. They float low in the water due to the sheer weight of the ice, which is why the tip of an iceberg is no measure of what lies beneath.
The International Ice Patrol has now traced where the iceberg that sank Titanic originated.
Greenland breeding ground
Eighty-five percent of all icebergs found in the North Atlantic come from the ice fjords on Greenland's west coast, and the ice shelf in Ilulissat is the most likely birthplace of the Titanic iceberg.
The iceberg that sank Titanic would have started life as a snowflake 15,000 years earlier. Snow that falls at the centre of the Greenland ice sheet is at first fluffy and not particularly dense, but it compacts with depth to become a third of its original size. Tens of metres below the surface it becomes so dense it turns to solid glacial ice.
An immense iceberg
In 1909, Ilulissat was producing just one or two of these huge icebergs each year. The iceberg that sank Titanic would have been up to a mile long, displacing around a billion tonnes of seawater.
It would have taken the iceberg over a year to edge its way down the 40-mile fjord. The relentless jostling of other bergs on this journey would have battered and eroded it, reducing it to half its birth weight.
Controlled by ocean currents
By 1911 the Titanic iceberg would have been picked up on the powerful west Greenland current and dragged down the north-eastern coast of Canada. It would have been huge, the above water ice alone rivalling the Colosseum in size.
Over a thousand miles from its birthplace and around a fortnight after its collision with Titanic, the last piece of the iceberg disappeared into the Atlantic ocean.