For decades, governments alone financed launching, operating, and returning space objects and humans. Scientific exploration of space propulsion, navigation, communication, and life safety advances resulted in commercially viable technologies and business methods. Scientific research and mission goals depended on government space mission priorities and budget appropriation processes. Government funding of exploration still predominates, outspending private sector investments. Commercial satellites are financed based on their terrestrial revenues and the risks of launch and in-service life. Space entrepreneurs are emerging with the wealth and explorer spirit to attract teams to do what governments and space industry contractors have not prioritized or funded: asteroid-hunting satellites, space tourism, space freight, lunar and asteroid mining, and habitats on the Moon and Mars. Concurrently, developing countries are launching satellites and missions, diversifying space entrepreneurship. Space finance is an inherent barrier or right. Space finance is a silent technology enabler or mission continuity risk. Space exploration is a unique setting to reimagine better space and terrestrial finance options and principles based on functional valuation models. Space law was written in the language of foreign policy and security concerns rooted in the Cold War Era. For more private sector financing to explore space, space law and transaction frameworks will need exploration and updating. Finance is essential to advance peaceful discoveries and uses of space assets. If exploring space is to be truly open to all humankind, then options for financing and insuring space explorers and missions must expand accordingly and inclusively, beyond governments and high net worth entrepreneurs. This article reviews relevant treaties and transactional frameworks for financing space operations. Historical context, principles, and inspirations are gathered from bank, finance, and market precedents of funding terrestrial exploration and development. The article summarizes transferable principles and practices of modern asset valuation models, transactional frameworks, and strategies for allocating project benefits and mitigating project risk. Based on such principles and precedents, the article identifies the challenges of, and suggests arrangements for, banking and finance of space-borne assets and activities. A space bank is described to prove that banking in space is viable and improves on terrestrial money flows for fragile regions affected by war, corruption, disaster, or breakdown of basic human rights. Weighing historical and modern context and space-based humanitarian and business continuity advantages, the article concludes by recommending that policymakers elevate space banking, finance, and insurance as topics of scientific inquiry, on par with other scientific explorations and technologies, to unleash a reliable future of human exploration of space.