110 | The Solar System |
Therefore, of the comets of Jupiter's comet-family, not only is none now retrograde, but none can ever become so unless some other body interfere with it.
ω nearly equals ω' in almost all cases.A singular coincidence characterizes the values and In all but two cases,nearly equals , as if for some reason were always trying to attain this maximum as a condition of stable equilibrium. In ten cases out of twenty, or in one half of the whole, the approach is within less than ½°.
Potential relative velocity remains unchanged.It is to be noticed that in orbits potentially retrograde, the potential direct velocity is also greatest; so that both on the score of retrogradation and of greater direct velocity, comets pursuing such orbits are more subject to expulsion.