<p>The Catholic Church is not opposed to space travel and exploration. On the contrary, it has always supported space projects, encouraging research on space stations and even considering the possibility of building new settlements on other planets. However, it maintains a principled position against assisted reproduction because, from its perspective, such practices always involve: (a) the destruction of human embryos; (b) the separation of the unitive act from the procreative one; (c) encouraging eugenic practices. In our view, this means that the Catholic Church cannot truly support a position in favor of human expansion into space (building new settlements and making other planets habitable), as such a policy could only be based on reproduction. In this article, however, we argue that space travel also presents another important issue for Catholics. If reproduction in space can only occur through asssted reproductive technologies, then Catholics should not have children. Therefore, it is legitimate to ask whether, from the perspective of the Catholic Church, the moral value of exploration and expansion in space can always prevail over the value of reproduction. Our conclusion will be that the answer depends on the kind of value one wants to assign to space missions.</p>