Attack on the Titanic! Scientists returned to the famous shipwreck they discovered almost 20 years ago. What they found may shock you

SuperScience, Oct, 2004 by Christy Brownlee

On the cold, dark night of April 14, 1912, more than 2,000 people sailed across the Atlantic Ocean on a giant cruise ship called the R.M.S. Titanic. With hardly any warning, the ship scraped a massive iceberg. As water rushed into the ship, passengers scrambled to board lifeboats. When the ship sank three hours later, more than 1,500 people died.

The world's most famous shipwreck lay undisturbed until 1985. That year, oceanographer (OH-shun-OG-ruh-fur) Robert Ballard and his crew discovered the Titanic's resting place deep in the North Atlantic. Harsh ocean conditions had caused the ship to corrode (kuh-RODE), and the crew suspected the damage would get worse over time.

Exactly how much has the ship corroded since discovery? And why? Last June, Ballard led a team of scientists back to the Titanic to find out.

Robo Photo

"This was a 'look, but don't touch' mission," said Jeremy Weirich, a scientist and member of Ballard's crew. To examine the ship without causing further damage, Weirich and other crew members guided underwater robots over the Titanic without touching it. A robot called Argus shined powerful lights through the dark ocean waters. Meanwhile, another robot called Hercules snapped photographs and video footage of the ship. Hercules also took readings of ocean pressure and salt levels to find out whether these conditions have a harmful effect on the Titanic.

The scientists then studied the photos and information. "It was like putting a puzzle together," said Weirich. Scientists could now see that both natural anti human-caused conditions have slowly damaged the Titanic.

Dangers of the Deep

Titanic lies in the abyssal (uh-BISS-uhl) zone, a part of the ocean about 4 kilometers (2.5 miles) below the surface. The conditions in this zone are so harsh that few creatures live here. No light makes it to the sea floor, and temperatures hover around a chilly 2[degrees] Celsius (35[degrees] Fahrenheit).

The conditions in this zone also make it tough for a shipwreck. According to Dwight Coleman, a scientist and member of Ballard's crew, the pressure of the water here is so strong that it's pushing Titanic into the ocean floor. "It's like there's an elephant standing on every square inch," he said.

The high levels of salt in the ocean also play a role in the ship's breakdown. Much of the Titanic is made from a metal called iron. When iron is placed in water, it will corrode over time. However, when salt is present in the water, the metal corrodes a lot faster.

The Titanic's metal has also been a tasty meal for "rusticles," bacteria that eat iron. The rusticles form drippy colonies that look like rust-colored daggers on almost every part of the wreck.

Harmful Humans

Although the ocean conditions are the leading cause of the ship's breakdown, scientists spotted evidence that human visitors--both tourists and explorers--are also to blame. Telltale markings show that submersibles (sub-MUR-sih-buhls) have landed on the ship's deck, adding strain to the already weak structure, and causing it to break. "It would be a lot like landing a helicopter on an old house," said Weirich.

Many of these visitors have also taken pieces of the ship. More than 6,000 artifacts have been removed since the ship's discovery. The only good news about this? Many of these artifacts will be restored and shown in museums.

The Titanic's Future

So how long until the Titanic completely disappears? No one knows for sure, but many researchers believe that the famous shipwreck could be around for several more decades. Keeping visitors from disturbing the wreck may keep the ship intact much longer.

In the meantime, scientists hope to document everything they can about the ship before it's destroyed. "It's like a museum down there, and it's not going to be there forever," said Coleman.

Words to Know

iceberg--floating chunk of ice

oceanographer--a scientist who studies oceans and the plants and animals that live in them

corrode--to break down a material

pressure--a pushing force

abyssal zone--a part of the ocean about 4 kilometers (2.5 miles) below the water's surface

bacteria--creatures too small to be seen by the naked eye

submersibles--underwater vehicles

artifacts--objects used by humans long ago

SCIENCE CONTENT STANDARDS

For Grades K-4

* Properties of Earth materials

* Properties of objects and materials

For Grades 5-8

* Structure of the earth system

* Properties and changes of properties of matter

INTEGRATE YOUR CURRICULUM!

Language Arts--Reading comprehension

BEFORE READING

Set a Purpose

To learn how ocean conditions can affect a shipwreck.

Background

* R.M.S. stands for Royal Mail Ship. These ships had cargo space to carry mail across the Atlantic Ocean.

* The Titanic's designers wanted it to be luxurious and comfortable; they never claimed it was unsinkable.

* Recently, the United States and Great Britain have signed a treaty to protect the Titanic as a maritime memorial.

Discussion Questions

* Why do people go to museums? (Possible answers: To learn about history: to learn about a special event; to see works of art.)