The size of the smallest known inner moons around the outer planets increases with distance from the Sun, but this trend is thought to be due to increasingly difficult lighting and observing conditions rather than any physical trend.
已知的外行星最小內衛星尺度著與太陽距離的增加而增加，但這一趨勢被認為是照明和觀測條件越來越困難所導致的，並非物理性質上的趨勢。