Essai sur la théorie des satellites de Jupiter, suivi des tables de leurs mouvemens, déduits du principe de la gravitation universelle
Paris, Nyon, 1766
In-4 de LIII, (3), 144 pages et 2 planches repliées [sans les 44 pages de tables de Jupiter par Jeaurat] ; basane marbrée de l'époque. Item #4014
Première édition, peu courante, de cette étude des mouvements et des perturbations des quatre satellites galiléens, les seuls connus alors, de Jupiter d'après la nouvelle théorie astronomique que Clairaut avait appliquée à la lune.
Il s'agit du premier essai visant à déterminer par l'analyse les principales inégalités du mouvement des quatre satellites de Jupiter.
Malheureusement pour Bailly, la même année, Lagrange publia un mémoire sur le même sujet qui éclipsa (de manière légitime celui de Bailly, qui ne prenait ni en compte l'action mutuelle des satellites entre eux, ni l'applatissement de Jupiter) totalement la publication de l'Essai de Bailly.
Une oeuvre peu connue, mais importante dans l'histoire de l'étude de Jupiter.
Les 44 pages de tables de Jupiter par Jeaurat n'ont jamais été reliées dans cet exemplaire.
"Bailly approached the problem of inequalities in the motions of the four known satellites of Jupiter with Clairaut’s lunar theory in mind. Improvements had been made in tables of the motions since Cassini’s 1668 ephemerides, but these improvements had been made empirically. Bailly was the first to attempt to achieve better tables theoretically, by treating each satellite in turn as the third body in a three-body problem. His success was not complete—there were considerable discrepancies between his theoretical formulation of orbitary elements and their observed values—but he did demonstrate that the problem was amenable to solution by Newtonian principles.
Bailly’s memoirs sparked interest in this subject, and the Acadèmie made it the topic of its essay contest for 1766. As an Academician, Bailly could not win the prize; nevertheless, he considered himself in competition with the astronomers who entered, and therefore synthesized and extended his earlier researches to produce his major Essai Although excellent, this work was greatly overshadowed by the prize-winning entry of Lagrange. As Bailly himself later admitted, Lagrange’s use of the new method of the variation of parameters allowed him to resolve almost completely the problem of five simultaneously perturbed bodies, as opposed to his own continuing series of three-body treatments." (Encyclopedia).
Price: €380.00