In the series "Ancient Authors" of my publications, I include a peculiar astronomical poem composed in the third pre-Christian century by Aratus, a poet and meteorologist from Syllus in Asia Minor of Cilicia.

The volume PHENOMENA and DIOSEMIA is the result of collaboration between two individuals who have mutual respect built over many years; both of whom have my personal esteem. One is my contemporary and old friend, Stavros Avgouloupis, specialized in astronomy topics and a recognized classical scholar; the other is the senior member of my team of collaborators, Theodoros Mavropoulos, a well-known translator, commentator, and analyst of ancient Greek literature.

An astronomical poem could not be effectively processed without the collaboration of an astronomer and a philologist. Through their cooperation, the two expert individuals provided us with a result that would not have been easy for either alone to achieve.

Their collaboration gives us the opportunity to observe and enjoy the starry sky and to affirm the well-known exclamation: "Great art Thou, O Lord, and wondrous are Thy works; Thou hast made all things in wisdom!"