Psychological horror in space, with an intriguing premise.
Our Earth is one of many, but the only where the ghosts of its inhabitants encircle it, keen to leap into the minds of those who leave the Earth, and in doing so push out some memories of the host. The protagonist is a volunteer, who is shield for those who travel off Earth, willing to have their memories overwritten to make space for the ghosts who they absorb to protect the crew. He has a reason for doing so – obliterating memories he no longer wishes to have.
There’s a clever layer to the story in terms of just who his mind is co-habiting with, and the crux of the story is in their finding yet another Earth, but one which is harboring something quite dangerous. The relationship between two of the crewmembers gives another dimension to the story, which is a tense one which grips.