Donato Creti’s Astronomical Observations , eight Vatican paintings, were made for Pope Clement XI on the basis of a plan by his general, Luigi Ferdinando Marsili. At that time, Marsili had been asking the Pope for support to establish the Istituto delle Scienze in Bologna. Using newly discovered documents from 1711, this study reconstructs the early history of the series. The iconographic program of Astronomical Observations is attributed to Eustachio Manfredi, an astronomer and poet of the Accademia dell’Arcadia. This study analyzes the structures and functions of these paintings, thereby revealing their significance, especially compared to the representation of the telescope at the end of the Baroque era, and to the taste and ideology of the same academy to which Clement XI also belonged.