Cassini is giving us a unique insight into the origin of planets. |
In reality, the satellites always experience each other's gravitational effect. If we were very restricted in our observations then we could observe the changes in the semi-major axis to get the ratio of the two masses and then use observations of the closest approach distance to get the sum of the masses, allowing us to solve for each. This is all based on the dynamics of the three-body problem. |
The structures we observe with Cassini are strikingly similar to those seen in many numerical models of the early stages of planetary formation, even though the scales are dramatically different. Cassini is giving us a unique insight into the origin of planets. |