Imagine looking for something tiny, like an earring, on a
football pitch in total darkness. That's a bit like looking for the
wreck of the Titanic in the middle of the huge Atlantic
Ocean.
People had been searching for the Titanic since it sank
in 1912. It was the most famous ship of all time and explorers were
desperate to find it.
Why was the Titanic so famous? It was the biggest ship
in the world. When it was built, people said it was unsinkable. On
its first voyage, the Titanic sailed for just 4 days
before it hit an iceberg and sank. Over 1,500 people lost their
lives.
Scientists and explorers competed to find the Titanic.
One scientist even wanted to take his pet monkey called Titan on a
mission to find the wreck! It took over 70 years for explorers to
find the Titanic.
Finding the Titanic
Robert Ballard was a deep sea explorer with a dream to find the
Titanic. The US Navy asked Ballard to find and
photograph two sunken submarines in the Atlantic on a secret
mission.

Robert Ballard, ocean
explorer
When Ballard looked for the submarines he realised a crucial
piece of information. When a vessel sinks, the wreckage is carried
by undersea currents. This leaves a trail of debris like the tail
of a comet.
In 1985, Ballard and his team were sent by the US Navy to
photograph the submarines again. This time, the US Navy let them
search for the Titanic afterwards.

Titanic wreck
The traditional way to search for wrecks was to use sonar. Sonar
uses sound to detect objects underwater. As well as using sonar,
Ballard searched for the Titanic's trail of debris. He
estimated that it would be over 2km long. Ballard had just 12 days
to find it, in an area of ocean five times the size of New
York.
To find the trail, Ballard used a deep-sea vehicle called Argo.
Argo had lots of cameras and was towed behind the ship. Argo
floated just above the sea floor, 2.5 miles down in the cold, dark
Atlantic.
After days of searching, Ballard found the trail. He knew the
currents would take the trail northwards. Ballard followed the
trail and sailed right up to the Titanic!
A year later, Ballard came back to the wreck of the
Titanic. He used a small submarine to travel to the wreck
and take pictures. It took two and a half hours for Ballard and his
team to reach the wreck. They were the first people to visit the
wreck of the Titanic.
James Cameron, director of the film Titanic, recently became the
first person to reach to travel
solo to the bottom of the Mariana Trench. The Mariana Trench is
the deepest part of the oceans, 11km beneath the surface. With
deep-sea science advancing even further, where will we go next?