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The Titanic: Facts About the 'Unsinkable' Ship

When it was built, the Titanic was the largest moving human-made object in the world. It had many new features, including remotely sealable compartments that led to it being deemed "unsinkable." Alas, it was not.

About the ship

The RMS Titanic was built by the White Star line, which was a competitor to another shipbuilding company, Cunard. In 1907, Cunard made major waves by building the Lusitania and the Mauretania, which set speed records crossing the Atlantic. To compete, White Star Line decided to build several large vessels known for their comfort instead of their speed, according to the Encyclopedia Britannica: the Olympic, the Titanic and the Britannic.

The Titanic was completed in 1912 at a cost of $7.5 million in Belfast, Ireland (although nowadays it's Northern Ireland). It took more than two years to build, and two workers died during its construction. The ship was 882 feet (270 meters) long, or more than four city blocks, and more than 92 feet (28 m)high. It weighed an incredible 46,000 tons. [Titanic Quiz: Fact or Fiction]

The Titanic began its journey in Southampton, England, and then sailed to Cherbourg, France, and Queenstown, Ireland (now known as Cobh). It sped west toward New York on April 10. It was carrying a total of 1,316 passengers and 885 crew members, according to the Encyclopedia Titanica. The people were a mixture of wealthy individuals as well as immigrants from Ireland, Germany and elsewhere.

On April 14, a nearby ship, the Californian, sent a message at 10:55 p.m.: "Ice report: We are stopped and surrounded by ice." But the captain of the Titanic, Edward Smith, and First Officer William Murdoch did not heed these warnings, steaming ahead near full-speed.

The known route of the Titanic and a possible route of the iceberg.
The known route of the Titanic and a possible route of the iceberg.
Credit: Texas State University

Sinking of the Titanic

At 11:40 p.m. ship's time, watchmen aboard the ship spotted an iceberg, and the ship made a sudden turn to the left, causing it to sideswipe the iceberg. The ice punched holes in the starboard (or right side) of the boat, along a nearly 300-foot (90 m) stretch and it began filling it with water. Six of the ship's 16 water-tight compartments started filling. But this was enough to make the ship begin to sink into the water, at which point the water flowed of the top of these compartments (the "transverse bulkheads") and begin filling the other compartments. Modern estimates suggest that the boat could have possibly limped to shore with only four breached compartments. [Video: How Exactly Did Titanic Sink? - With James Cameron ]

With six compartments leaking, however, the Titanic's fate was sealed — it had lost too much buoyancy to remain afloat, and the fact that it was a well-built and durable ship at this point made little difference. That said, the ship didn't sink for almost three hours, longer than Titanic's engineer gave it — when he heard that six compartments were leaking, he predicted it would only stay afloat for 1 to 1.5 hours, said Titanic expert Parks Stephenson. Contrary to some studies that say the Titanic had weak rivets, it was actually quite strong for its time, Stephenson said.

As the front filled with water and sunk into the ocean, the back of the ship lifted out of the water, according to analysis by James Cameron and eyewitness accounts. This placed tremendous pressure on the middle of the boat. It eventually cracked and the front of the ship crashed back into the ocean; the ship sank at 2:20 a.m. on April 15.

Why did the Titanic sink?

Many have speculated as to what led the Titanic to hit the iceberg. Stephenson said there was likely at the time an atmospheric effect called a "cold air mirage," which is relatively common in the North Atlantic, and helped prevent the crew from seeing the iceberg until too late. This effect may have also prevented nearby ships from seeing the Titanic's warning flares, or from discerning that they were signals of distress.

A ship called the Californian was nearby, likely within less than 20 miles (37 kilometers) of the Titanic, and was singled out for scrutiny for not responding to the Titanic's distress signals. But the ship had retired for the night, and its wireless system was turned off. The captain of the ship claimed that the flares his officers saw weren't thought to be distress signals. But it's unclear exactly why the Californian didn’t respond and continues to be a matter of some debate, Stephenson said.

The Titanic carried only 16 lifeboats as well as four "collapsibles," which in total could only accommodate a third the Titanic's total passengers had the ship been fully filled. As it was, it could have only accommodated half the passengers aboard. While this may seem unforgiveable by today's standards, the Titanic actually carried more lifeboats than necessary under the law at the time. In the aftermath of the sinking, laws were put in place to prevent this from happening again and required ships to carry more lifeboats.

[Infographic: Why and How the Titanic Sank]

Titanic passengers and survivors

All of the Titanic's survivors were rescued by the Carpathia, which received the Titanic's distress signal and immediately set off toward the Titanic. It didn't get there until about 4 a.m., however.

Of the 2,224 people on board, 1,514 lost their lives, while 710 survived. First-class passengers fared much better than those in third class. For example, only 3 percent of first-class women died, whereas 54 percent of third class women perished.

Some of the Titanic's passengers were prominent people, including John Jacob Astor IV, one of the wealthiest men in the world at that time. So were Ida and Isidor Straus, who was the co-owner of Macy's department store. And of course, there was "Unsinkable" Molly Brown, a socialite who became famous when she exhorted her lifeboat to return to look for survivors, and ultimately survived the ordeal herself.

Astor didn't survive, as he didn't take seriously the reports that the ship was sinking, and later wasn't allowed onto a lifeboat due to a "women and children first" policy. (His pregnant wife did survive, however.) Ida Straus initially boarded a lifeboat but returned to her husband. "Where you go, I go," she reportedly said. The couple would die together. (He was 67, she was 63.)

The wreck of the Titanic was discovered by Bob Ballard on Sept. 1, 1985. He used his underwater craft called Argo to follow a trail of debris to the ship's hull.

Email Douglas Main or follow him on Twitter or Google+. Follow us @livescience, Facebook or Google+.

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