https://www.amazon.com/Traveler-Dark-Ex-Situ-Book-ebook/dp/B0727XP4WJ
$0.99 (regularly $2.99) 5/10/2017 - 5/23/2017!
Sixteen hundred years ago, we fled Earth in search of a new home. Now our long journey may finally be at an end. None of us have ever walked on soil, felt rain, or breathed unrecycled air. It's been two hundred years since we explored the last potential planet. It was a failure.
Our resources nearly spent and our population dwindling, we sent a last exploratory mission to a new planet. It's ideal... but for the remains of an advanced civilization that suggests that they are not alone.
Now, we must make a choice. Do we sacrifice another civilization to save our own?