Titan’s tides point to hidden ocean

Titan's tides point to hidden ocean Nothing like it has been seen before beyond our own planet: large tides have been found on Saturn's moon Titan that point to a liquid ocean - most likely water - swirling around below the surface. On Earth, we are familiar with the combined gravitational effects of the Moon and Sun creating the twice-daily tidal rise and fall of our oceans. Less obvious are the tides of a few tens of centimetres in our planet's crust and underlying mantle, which floats on a liquid core. But now the international Cassini mission to Saturn has found that Titan experiences large tides in its surface. "The important implication of the large tides is that there is a highly deformable layer inside Titan, very likely water, able to distort Titan's surface by more than 10 metres," says Luciano Iess of the Università La Sapienza in Rome, lead of author of the paper published in Science magazine. If the moon were rigid all the way through, then tides of only one metre would be expected. The tides were discovered by carefully tracking Cassini's path as the probe made six close flybys of Saturn's largest moon between 2006 and 2011.