As environmental, political, and public health crises multiply on Earth, we are also at the dawn of a new space race in which governments team up with celebrity billionaires to exploit the cosmos for human gain. The best-known of these pioneers are selling different visions of the future: while Elon Musk and SpaceX seek to establish a human presence on Mars, Jeff Bezos and Blue Origin work toward moving millions of earthlings into rotating near-Earth habitats. Despite these distinctions, these two billionaires share a core utopian project: the salvation of humanity through the exploitation of space. In Astrotopia, philosopher of science and religion Mary-Jane Rubenstein pulls back the curtain on the not-so-new myths these space barons are peddling, like growth without limit, energy without guilt, and salvation in a brand-new world. As Rubenstein reveals, we have already seen the destructive effects of this frontier zealotry in the centuries-long history of European colonialism. But Rubenstein does more than expose the values of capitalist technoscience as the product of bad mythologies. She offers a vision of exploring space without reproducing the atrocities of earthly colonialism, encouraging us to find and even make stories that put cosmic caretaking over profiteering.