Interior structure of planets - New insights

The discoveries of thousands of extrasolar planets in our galaxy raise fundamental questions about formation, composition and interior structure of planets. In traditional models of planetary interiors the planets are structured in 2-4 distinct layers of different composition (iron, rock, water, gas), similar to the Earth. However, new theoretical and observational evidence suggest that in general planetary interiors may be very different from this simplified picture. I will show some of these new findings and discuss how we expect planetary interiors to look, based on recent planet formation and evolution models.