of several 109 yr. however， the effect of the possible instability of the orbit of mercury may not fatally affect the global stability of the whole planetary system owing to the small mass of mercury. we will mention briefly the long-term orbital evolution of mercury later in section 4 using low-pass filtered orbital elements.
the orbital motion of the outer five planets seems rigorously stable and quite regular over this time-span (see also section 5).
3.2 time–frequency maps
although the planetary motion exhibits very long-term stability defined as the non-existence of close encounter events， the chaotic nature of planetary dyna
对火星轨道变化问题的最后解释(26/49)