This is a drawing showing the composition of the interior of Pluto.

The complex molecules probably come from radiation, which forces new molecules to be created from the surface of Pluto.

Pluto's interior is primarily composed of water ice of different phases. The drawing shows a possible layout of the different phases of ice in Titan's interior. In this respect, Pluto is very much like other icy moons.

Deep inside Pluto are to be found the more heavier, rocky elements such as silicates. These form the core of Pluto.