Studying science in the Ottoman, and indeed in any other non-Western, context is often deemed unthinkable without relating the subject in question to a real or imaginary Western/European connection. Any study on astral sciences in the early modern Ottoman or Islamicate context, for instance, is expected to address the question of heliocentrism (or lack thereof), to refer to the possible contributions of Ottoman/Muslim achievements to the works of Copernicus and Galileo, or to exemplify at least the "cross-cultural exchanges" with their Western/European counterparts. Calls for writing a global history of science in the early modern era may sound in the first place as a welcome development. However, many a time, the global histories of science quickly turn into bodies of narratives reminiscent of nineteenth-century world fairs where the individual pavilions of non-western nations representing the exotica (read "achievements") of their home cultures serve only for feeding the hegemony of the host country in the West. What is, thus, sorely needed is treating the local contexts of scientific production and consumption in the Ottoman and/or Islamicate world on their own terms without necessarily measuring their value against any standard imposed by considerations of science in the Western/European context. As a case study, I will focus in this paper on the genre of the astrological almanacs (taqwim), a truly global form of scientific writing that bears crucial local insights into understanding the culture and politics of astral sciences in the early modern Ottoman context. By looking at the production process of these annual tables based on daunting mathematical/astronomical calculations and at the reception of the astrological predictions by their target audience, I will demonstrate how these sorely untapped sources from the fifteenth through even the twentieth century can indeed reveal the multi-layered nature of astral sciences in a local Muslim empire.