I was curious if someone knows the titles of the trilogy of a book series where a planet is inhabited by people who landed from ships from Earth after it was destroyed. On the planet there is only the metal from what was brought, and no trees and the water is toxic until people are genetically engineered to live there.
That's the Children of the Star trilogy by Sylvia Engdahl:
The refugees were explicitly not from Earth; in the authors notes to the trilogy printing I have, she mentions that it's clear from the description (6 habitable planets in the home system) that it isn't Sol.
Excellent series; although they can be clunky at times, it's good Speculative Fiction with neat ideas.