The applet at right simulates a sample of gas atoms in a planet's atmosphere. The bottom corresponds to the planet surface and the top, outer space. When an atom leaves to the left or right, it comes back immediately on the other side. When an atom leaves the simulation out the top, that atom is lost from the planet.

Any gas at non-zero temperature consists of an ensemble of atoms with different energies, moving in random directions. In the simulation below, you will see cases of an atom suddenly changing direction as if something ran into it with no other atoms nearby. This is because the simulation shows only a very small sample of the actual number of atoms in an atmosphere, representatives of the entire atom population.

The slider at left represents gravitational strength of the planet. Slide it up to simulate a larger planet like Jupiter, down to simulate a smaller body like Earth's moon. The button at the bottom of the applet allows you to inject, from the surface, another sample of atoms. This represents outgassing of a planet due to volcanism or release of submarine gasses (such as the occurence of clathrate hydrates in the sediments under the Bermuda Triangle.

Planetary Atmosphere Simulation