Changes in the spin rate of Saturn's moon Titan suggest an ocean of liquid water lies beneath its icy surface, a new study reports. The finding bolsters the possibility that the moon might foster life.

Titan's low density suggests it is composed of a combination of water and rock. During the moon's early days, heat from its formation and the decay of radioactive material should have melted much of this water to create an ocean.
Much of the ocean would have since frozen. But scientists suspect a liquid layer up to 300 kilometres thick persists beneath an ice crust, probably aided by ammonia, which acts as an antifreeze.