A "man on the moon" is a person who is not an outcast but different from everyone else. A unique person, different in a good way.

“月亮上的人”（man on the moon）指一个并不离群索居、但与其他人不一样的人。他独一无二，很特别，而且是好的特别。

例如：

That guy in the corner is a man on the moon heard he was actually really cool.

角落里那个人是个很不一样的人，听说他真的非常酷。