“银河系”的英语可以翻译为：Galactic System，galaxy，Milky Way system，Milky Way galaxy ...

“银河系”的拼音为：yín hé xì...

由此你可以算出银河系的总质量。From this you can calculate the total mass in the Galaxy.银河系由1,000亿颗恒星组成。The Galaxy consists of 100 billion stars.地球是银河系中的星球之一.The earth is one of the planets in the Galaxy....