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Titan moon's huge methane seas

Measurements of a big sea on Titan, a moon of Saturn, show that it contains about 9,000 cu km of mostly liquid methane.

This huge volume is equivalent, say scientists, to about 40 times the proven reserves of oil and gas on Earth.

The extraordinary thing is that Ligeia Mare is only the second largest hydrocarbon sea on Titan.

The body of liquid methane known as Kraken is perhaps five times as big.

Randy Kirk, a US Geological Survey scientist working on the Cassini mission at Saturn, spoke to our correspondent Jonathan Amos.

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