Posterra is not yet an 'official' organization with any fixed members. ... An open invitation exists to discuss and refine Posterra 's structure--before its official founding. Posterra seeks those who believe that humankind must grow the capacity to create human settlements off of the planet Earth, and that the broadest segment of humanity possible must be included within it. ... Currently, Posterra is an idea for which the boundaries and structure are not yet rigidly defined. ...