Great pop-science book on off earth space settlements. Examines more factors in taking human life into space and/or other planets than I ever considered.
Just re-enforces my belief that we need to fix our planet.

I recommend this book. It covers US history that was never taught in the high school curriculum. It is dense with information and has a good bibliography on references used. I did have to take breaks from reading it, reading something lighter in subject matter, because of the intensity of the abuse ravaged upon indigenous people by the European invaders, then the continuing abuse of later immigrants to the USA who were not white.