42 light years away from Earth there is the planet GJ 1214 b orbiting a red dwarf. This planet is a super-Earth with a radius of 2.7 Earth radii and 6.5 Earth masses. Knowing the radius and the mass of the planet we automatically also know its density: 2 g/cm3 (for comparison: the Earth has a density of 5.5 g/cm3). This makes it a first class candidate for an ocean planet and spectral analysis of the planet's atmosphere seems to confirm this fact. But this world is different from what you might think: because of its closeness to its star it has a temperature of about 190 °C and the surface pressure below the thick atmosphere is much higher than here on Earth. Under these conditions GJ 1214's water is not really comparable with the water we know from our own planet: there is "hot ice" (solidified water at high temperatures) or "superfluid water" (water which behaves like a fluid with zero viscosity) in the oceans of this planet.