Astronomical authority is the main concept of authority in the Astronist religion, comparable to the concept of the authority of God in other religions. Astronists state that astronomical authority is the only real and knowable authority for humankind and that being subject to the authority of the astronomical world is an inescapable fact of human existence, whether a person particularly believes in the authority of the astronomical world or not. 

Rather than being considered a subset of natural authority, astronomical authority is referred to in Astronism as the authority under which terrestrial nature itself is commanded. With this, Cometan highlights the first time in which the astronomical world is not only made distinct from the natural world, but is positioned as being above the natural world in physical superiority.

Often, concepts of astronomical authority are expressed through examples like the possible impact of an catastrophic asteroid to The Earth or the authority of The Sun for the continuance of life on The Earth. These concepts do have pre-Astronist origins, likely at some point within the Astronic tradition (although clear origins have yet to be pinpointed), but they were not formally intergrated into a belief system until Cometan's incorporation of them into the worldview of Astronism through this concept of astronomical authority.