Astronism emerged as a naturalistic religion or organised philosophy out of the early 21st century Space Philosophy movement while modernism began approximately in the late 19th and early 20th centuries following dramatic changes in mainly Western society whose cities were growing rapidly and whose towns were industrialisation. Particularly as a result of these economic developments which later lead to changes in social and cultural of different individuals and organisations and their roles in society, a distinctly modernist understanding of the world formed that had subsequent impact on philosophy, art, music, and other mediums of culture that have themselves made impacts on modern religion.

Postmodernism developed in the mid-to-late 20th century as a movement in response to and with aims of reforming modernism, but in recent decades, namely the first two decades of the 21st century, affiliation with postmodernism has declined, thus opening up an opportunity for a new movement to develop. Here, we introduce metamodernism, or post-postmodernism. Rather than acting as a rejection of postmodernism, metamodernism's aim is considered one of combination; that is, to combine modernism with postmodernism. In this sense, we can understand metamodernism as a synthesis of these two earlier movements that will subsequently form new ideas and approaches to culture and theory that were not achieveable by the prior two movements, perhaps in part to their polarity. 

Religions throughout history have developed in the nature and "personality" according to the place of their founding and their subsequent development. Astronism is not different in this regard because all genuine religions and philosophies are a reflection of the concerns, modes of thought, and theoretical approaches important at the time. Religions certain develop and may do so in such a way that in decades or centuries following their initiation founding, they become entirely different from what they were when they began, but there is no doubt that religions are formed in response to the questions of the time in which they were formed.

Astronism was founded by the philosopher Cometan in 2013 (known as The Year of The Gift) in the United Kingdom. Its ideas certainly do mirror some elements from both modernism and postmodernism as these two movements preceded it and formed the foundations to the thinking of the time in the early 21st century due to their engrainment in the previous century. As a result, Astronism does consist of both modernist and postmodernist ideas; in Astronist art, the dominant school is one in which cosmic phenomena is exaggerated and exentuated thus demonstrating a rejection or avoidance of realism. 

In the founding book of Astronism, the Omnidoxy, Cometan takes considerable time up to explore self-referential questions regarding both himself, what Astronism is, and what even the Omnidoxy itself is. In no other religious founding books do we see this same level of concern for self-referentiality. Cometan went as far to develop the discipline of Meta-Astronism (the study of what Astronism is), just a few years after Astronism was founded. Postmodernist thought is pungent throughout the text.

In other areas, postmodernist tendencies are evidential. The moral relativism that Astronism expounds through its amoralistic approach to morality systems presents itself as a religion whose tenets are not based on a determined and authoritative decreed code of morality, but instead a vague and largely liberal set of teachings, adherence to which is the basis for reward in some paradisical afterlife dimension, but instead, a personal choice which its Institution either encourages or does not, however rarely deplores. Finally, the distinct role of pluralism in the Astronist understanding is perhaps the most difficult to pinpoint, but it does exist within Astronism. 

The Institution's interfaith dialogue approaches to other religious organisations immediately following its establishment demonstrate its cohesive nature. The Philosophical Spirit, a concept or approach developed by Cometan, leads his followers to think openly, but with logically justifiable rationality for one's ideas and beliefs. Postmodern pluralistic influence on Astronism is also seen by the Astronist Institution's eager efforts to syncretise Astronism with other religions rather than to outright reject them (although calling for syncretism does not necessarily mean acceptance of those other religion's beliefs). 

In essence, Astronism is the combination of some modernist and some postmodernist approaches in one religion or system of thought and belief which may therefore best be described as metamodernist.