The object moved slowly in the sky like a distant planet.

VOA: special.2010.07.11

Suppose the planet were hit by a comet-- this happened--something like this happened sixty-five million years ago, so it could happen again.

假设这个星球被一颗彗星击中-,这样的事，大约六千五百万年前,发生过，所以它还可能再发生。

耶鲁公开课 - 金融市场课程节选

John Bachar said rock climbing felt like being on another planet.

VOA: special.2009.12.09

" planets like our own planet formed. So star formation is a very big thing for Herschel."

VOA: standard.2009.05.14