With Cyrano, Voltaire, and Verne, France provided important milestones in the history of early science fiction. However, even if the genre was not very common a few centuries ago, there were numerous additional contributions by French-speaking writers. In this paper, we review two cases of interplanetary novels written in the second half of the eighteenth century and sharing a rare particularity: their authors were female. Voyages de Milord Ceton was imagined by Marie-Anne de Roumier-Robert whereas Cornelie Wouters de Wasse conceived Le Char Volant. While their personal lives were very different, and their writing style too, both authors share in these novels a common philosophy in which equality -- between ranks but also between genders -- takes an important place. Their works thus clearly fit into the context of the Enlightenment.