The theologians seem to have recognized a special, nonrational–I wouldn’t call it irrational– aspect of the feeling of sacred or holy. They call it `numinous.’ The term was first used by… let’s see… somebody named Rudolph Otto in a 1923 book, The Idea of the Holy. He believed that humans were predisposed to detect and revere the numinous. He called it the misterium tremendum. Even my Latin is good enough for that. In the presence of the misterium tremendum, people feel utterly insignificant but, if I read this
right, not personally alienated. He thought of the numinous as a thing `wholly other,’ and the human response to it as `absolute astonishment.’ Now, if that’s what religious people talk about when they use words like sacred or holy, I’m with them. I felt something like that just in listening for a signal, never mind in actually receiving it. I think all of science elicits that sense of awe.
—  “Numinous" Carl Sagan, Contact