Emigrating Beyond Earth
Human Adaptation and Space Colonization
Cameron M. Smith and Evan T. Davies, MultCoCentral 919.904 S6442e 2012
This is an anthropological view of the eventual human migration into the cosmos, extrapolating from the Polynesian migration east into the Pacific ocean. An interesting addition to the economic, technical, astronomical, and biological characterizations of such a migration, but somewhat uninformed about those other constraints. Too concerned with objections to space travel, perhaps based on the assumption that the process will be outrageously expensive and require widespread consensus.
But "we" have already "migrated" to the planets, asteroids, and interstellar space with 20th century machines; what will 21st century or 30th century "machine" migration look like? When will machines evolve towards human-scale minds, or human minds develop machine-scale invulnerability? The "essence of human" is our DNA blueprint, a lifetime of memories, and a world of culture. Someday, we may be able to fit all of that into a very small and practically indestructable probe.
The authors reflect a widespread assumption - humans will live in gravity wells, even if those locations are extremely inhospitable to unarmored life and machinery, and lack the beneficiated resources and one gee acceleration humans and technology evolved for.
But "gravity" is easy to mimic with centrifugal acceleration. Radiation shielding is much easier in zero gee - you don't need heavy structure to support it overhead. Beneficiated resources? Oceans and life concentrate those on Earth; no other planet offers that, while unmixed asteroids have many different chemistries.
For now, humans live on and interact with the Earth's surface - 99.95% of the sphere is inaccessible. The asteroids we know about have more surface area than the Moon; the asteroids and comets we don't know about might have more surface area than Earth and the other rocky planets and moons.
So read the book for the anthropology, and imagine the much better book that could have been written if these intelligent and educated authors were liberated from their rock-bound assumptions.