Jupiter's Interior 

Jupiter is a "gas giant" -- mostly a ball of gas under pressure.

Primordial composition: mostly hydrogen and helium, like the sun. Why?

So what happens when you add mass to a pure hydrogen ball?


What does the interior look like? How does hydrogen behave under pressure?

Hydrogen Phase Diagram

Pressure ionization:

The pressure of a gas is a measure of its energy density. Enough energy will ionize hydrogen, so inside Jupiter, the pressure is sufficient to ionize hydrogen.

At this point gaseous H2 becomes a liquid metal H+. The electrons flow freely from atom to atom, like in a metal (conduction). What will this create?

At Jupiter's center, there is a rocky/icy core of about 15 Mearth (5% MJupiter).

Jupiter's Interior

Interior Heat

We can calculate Jupiter's equilibrium temperature based on its albedo and distance from the Sun. This turns out to be 110 K.

Jupiter's observed temperature is 125 K. Where is this extra heat coming from?
 
 

Gravitational Contraction!