Alvin the sub gets a makeover

A famous sub called Alvin that's explored more of the ocean floor than any other research vessel is to be put back into the water after a major upgrade.

The £26 million refit will now enable Alvin's researchers to reach 98% of the world's ocean floors.

The 49-year-old vehicle made a name for itself after making big discoveries like volcanic vents in the pacific.

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