Expanding and mapping the disc of the moon.
In February, 1645, the Dutch cartographer and engineer Michael van Langren (1598-1675) printed his Plenilunii lumina Austriaca Philippica, a single engraved lunar map of outstanding detail, and named the various craters Innocenti, Ferdinandi, Caroli, and other Habsburg titles. Like Galileo’s effort to name the Jovian moons after Cosimo de’ Medici, this simply did not last. By 1651, the monumental Almagestum Novum of the Jesuit astronomer Giambattista Riccioli (1598-1671) established our accepted nomenclature, grafted onto the map of his friend, student, and collaborator, Francesco Maria Grimaldi (1618-1663). In the process, most of the names Hevelius had given the craters and seas were quietly ignored. Mons sanctus became Firmicus, Mons Aetna became the crater Copernicus and the Lacus Hercules was replaced by Rheticus and Stadius. Rather loosely, it reads as a parallel to Riccioli’s chronological outline of astronomy: the ancient names of Zoroaster, Endymion and Atlas are in Octant III; Thales, Plato and Eudoxus inhabit Octant II; Hipparchus and Ptolemy are positioned near the center, and the names of Clavius and Tycho Brahe are given to prominent craters in Octant VI. Traces of van Langren remain: the small crater he named after Alessandro Piccolomini (1508-1579) still marks lunar maps today.
Due to libration, the disc has been expanded with craters and seas that cannot always be seen. Really, the names Riccioli gave to the dark plains of basalt are still beautiful, after the passage of centuries: seas of tranquility and nectar, turbulent oceans of storm. Ultimately, Riccioli’s adaptation of a modified Tychonian model for the solar system made his great book less important to the historiography of astronomy after Jean-Étienne Montucla, even though it contained the most detailed treatment of the controversies surrounding heliocentric cosmology written in the seventeenth century.