Halley's Comet, for example, is usually very bright when it passes through the inner Solar System every seventy-six years, but during its 1986 apparition, its closest approach to Earth was almost the most distant possible.
以哈雷彗星為例，在76年的週期中，當進入內太陽系時它通常都很明亮，但是在1986年接近太陽時，它與地球的距離卻可能是最遠的一次。