Answer:
the energy emission process is due to nuclear fusion
Step-by-step explanation:
In the planetary system the energy emitted by bodies is a part of the energy received by a hot body (star), this star is what creates the entire energy cycle of a given planet. This creates the entire tidal movement, continental drift
If the planets reach a certain size the gravitational force near their center is so great that the atoms are crushed and some beginnings of fusion processes are formed where some atoms are transformed from hydrogen to helium releasing a certain amount of energy and heat that believe that the planet emits more energy than it receives from its star.
In summary, the energy emission process is due to nuclear fusion