| 释义 |
冥王星míngwángxīng太阳系九大行星之一,按离太阳由近而远的次序计为第九颗,公转周期约为248年,自转周期约6.4天。是九大行星中最小的行星。{Pluto; smallest one of the nine planets of the solar system, of the farthest mean distance from the sun, with its period of revolution being about 248 years and period of rotation being about 6.4 days;} |