Triton submarine test dive
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Race to the bottom of the ocean

The depths of the world's oceans are luring a new generation of explorers keen to match and exceed the exploits of those who have gone before them.

The BBC's Rebecca Morelle joined the team from Triton submarines as they race to become the first to reach the deepest place in the ocean - the Mariana Trench.

  • 23 Feb 2012