Sixteen physical parameters of a Galilean moon collectively with the other three moons obey a conservation equation on the surface of an elliptical cone and the numbers of parameter groups in five categories constitute a pyramid or Pascal triangle accurately. The maximum error for the formula is less than 0.29%. Color balls on the cone stand for points of parameter groups. They are plotted using symmetry of the equation. Fundamental parameters, such as time, space, mass, gravity, and energy, are neutralized into a single variable.