In this essay we present a tentative archaeoastronomical analysis of the Moxos' Lagoons, a controversial and huge geographical network in the landscape of the Bolivian Amazon. In the late 1990s, a preliminary analysis of the orientation of a comprehensive and statistically significant number of lagoons showed that only human action could explain the peculiarities of their geometry, and especially their orientation according to a main axis aligned to an azimuth of 50° and its complementary angle. Since then, there has been an open debate on how these orientations could have been determined in practice. The absence of distinctive geographical features on the horizon strongly suggests that this peculiar pattern must have an astronomical justification. This short report presents a first approximation to the problem, suggesting that the lagoons could have been deliberately orientated in accordance with certain stellar positions which may have marked selected moments in the local climatic or economic cycle, a fact that could be corroborated by ethnohistoric references. The implications for new ethnographical research in the region are self-evident.