冥王星在太阳系外宇宙有着它自己的家族。

Pluto has family in the outer solar system.

youdao

整个宇宙拥有十亿多个河外星系，一个河外星系就是一座星城，每座星城有“居民”上千亿颗。

Our Universe contains over a billion galaxies; star cities each with a hundred billion inhabitants.

youdao

整个宇宙拥有十亿多个河外星系，一个河外星系就是一座星城，每座星城有“居民”上千亿颗。

Our Universe contains over a billion galaxies; star cities each with a hundred billion inhabitants.

youdao