Rhys supposes that a different planet could have come to call itself Earth, or that could be a translation issue.

He's really not sure how translation here works, but there has to be something, because it's not like anyone outside of Umayma speaks Nasheenian or Chenjan. The language of the Kitab, perhaps, but that's not what Rhys is trying.

"Umayma was made habitable three thousand years ago. Before that, my people lived on the moons. Before that, if you go back far enough, what we called Earth."