What do we need to ask before settling space?

We advocate for a humanitarian review of space settlement proposals, which takes seriously the various cultural and ethical questions that space settlement raises. As a preview of how such a review might be conducted, we discuss five rationales or objectives for space settlement (for long-term human survival; for resources; for scientific knowledge; for adventure; and for spiritual insights). We argue that none of these rationales escapes the need for thorough scrutiny, because each rationale raises challenging and distinctive cultural and ethical questions during all phases of the settlement process. Of particular relevance here are questions concerning who gets to participate in settling space as well as who benefits from the endeavor. Thus, regardless of our rationale for settling space, we will not do so ethically unless we continually subject our decision-making to critical scrutiny, not only on Earth during the planning phase, but also while settlers are in-transit and throughout the settlement's founding and growth. © 2021 British Interplanetary Society. All rights reserved.