The diamond oceans of Uranus and Neptune

Neptune and Uranus may have diamond icebergs floating atop liquid diamond seas closer to home. The surprise finding comes from the first detailed measurements of the melting point of diamond, Discovery News reports.

Scientists zapped diamond with a laser at pressures 40 million times greater than the Earth's atmosphere at sea level, and then slowly reduced both temperature and pressure. They eventually found that diamond behaves like water during freezing and melting, and that chunks of diamond will float in the liquid diamond.

The full story is here, with pictures, and I thank Gregory Rehmke for the pointer.  Don't think, however, that a commercial mission to these planets could pay for itself — elasticity of demand!