Naming the Satellites of Jupiter and Saturn

Naming the Satellites of Jupiter and Saturn Albert Van Helden he naming of Jupiter's and Saturn's satellites after his patron, the Duke of Brandenburg-a sug- 7provides an interesting example of how such gestion followed by no one. Third, he suggested matters were handled before twentieth-century in- naming the outermost satellite "the Saturn" of Ju- stitutions were created to deal with them. As the piter, the next one "the Jupiter" of Jupiter, the discoverer of Jupiter's moons, Galileo claimed the third one "the Venus" of Jupiter, and the inner- right to name them. He wished to name them most "the Mercury" of Jupiter. This cumbersome his parrons, the lviedici family, and asked system never caught on. Finaiiy, Marius related a whether they would prefer "~osmi;Stars" (afier kggestion- - by ~epler: Cosimo 11, drand ~ukeof~uscan~) or "Medicean Jupiter is much blamed by the poets on account Stars." They opted for the latter, and through much of his irregular loves. Three maidens are espe- of the seventeenth century the satellites were known cially mentioned as having been clandestinely by that name. In his notebooks, Galileo referred to courted by Jupiter with success. 10, daughter of them individually by number, starting with the the River Inachus, Callisto of Lycaon, Europa of satellite closest to Jupiter, but he never had occa- Agenor. Then there was Ganymede, the hand- sion to refer to them in this way in print. some son of King Tros, whom Jupiter, having In Provence, Nicholas Claude Fabri de Peiresc taken the form ofan eagle, transported to heaven tried to differentiate between the Medicean Stars on his back, as poets fabulously tell.. . I think, by assigning them the names of individual mem- therefore, that I shall not have done amiss if the bers of the Medici family, but this system was not First is called by me 10, the Second Europa, the published and thus was never used by others. In Third, on account of its majesty of light, his Mundus Iovialis ("Jovian World") of 16 14, Ganymede, the Fourth Callisto.. . Simon Marius went into the naming problem in This fancy, and the particular names given, some depth. First, he himself used the numerical were suggested to me by Kepler, Imperial As- system beginning with the satellite closest to Jupi- tronomer, when we met at Ratisbon fair in Octo- ter. Second, he thought that he might call them ber 1613. So if, as a jest, and in memory of our

I 1 friendship then begun, I hail him as joint father Al Van Heiden, an historian at Rice University, of these 'four stars. again I shall nit be doing specializes in Galileo and his times. Among his wrong. [A. 0. Prickard, tr., "The 'Mundus publications are "The Invention of the Telescope," Jovialis' of Simon Marius," The Obsentatory, 39 Trans. American Phil. Soc., Vol. 67, Pt. 4, 1977, (1916), p. 380.1 and a translation of Galileo's Sideteus Nuncius, U. None of these suggestions caught on because Chicago Press, 1989 (available in paperback). Chs Notes continues on page 2 - Class Notes continued from page 1 - with Jupiter's satellites, there was no confusion in the numbering system. Following Galileo and SIDEREAL MESSENGER Marius, astronomers simply referred to them by unfolding great and very wondrous sights number, beginning with the innermost satellite. and displaying to the gaze of everyone, With the satellites of Saturn, however, a problem but especially philosophers and astronomers, developed. In 1655 Christiaan Huygens discov- the hngs that were observed by ered the first and largest (Titan); then in 1671-72 GALILEO GALILEI, Giandomenico Cassini discovered two more Florentine patrician (Iapetus and Rhea), and in 1684 yet another two and public mathematician of the University of Padua, (Tethys and Dione). These five satellites were num- with the help of a spyglass lately devised by him, bered like their Galilean counterparts. But when about the face of the Moon, coundess fixed stars, in 1789 William Herschel discovered two addi- the Millo/ Way, nebulous stars, tional satellites (Enceladus and Mimas) internal to but especially about the first, confusion followed. Did one now renum- four planets flying around the star of Jupiter at uneqd intervals ber them all (thus causing confusion for those who and periods with wonderful swiftness; consulted older works), refer to the two new ones which, unknown by anyone until this day, as nos. 6 and 7 (thus making the order of the the first author detected recently satellites confusing), or refer to them by order of and decided to name discovery? Herschel's son, John Frederick Will- MEDICEAN STARS iam, suggested in 1847 that Saturn's satellites be given individual names of mythological figures as- Tide page of Galilee's Siderw Num'w, as translated by sociated with Saturn, after the suggestion made by Albert Van Helden. Marius for Jupiter's satellites: As Saturn devoured his children, his family could not be assembled around him, so that the "Kepler's Laws, So-Called choice lay among his brothers and sister, the Titans and Titanesses. The name Iapetus seemed - Addendum - indicated by the obscurity and remoteness of the Curtis Wilson has sent the following note per- exterior satellite, Titan by the superior size of the taining to his "Class Notes" column in the last Huyghenian, while the three female appellations issue, HAD News 3 1: "Owen Gingerich informs [Rhea, Dione, and Tethys] class together the me that, thirty years before Robert Small, Joseph- three intermediate Cassinian satellites. The JCrbme Le Franqais de Lalande, in his AbrPgk minute interior ones seemed appropriately char- d%tronomie of 1774, listed Kepler's Laws with acterized by a return to male appellations the same numbering we use today. The AbrkgPis a [Enceladus and Mirnas] chosen from a younger condensation of Lalande's Rrtronomie-the chiefi and inferior (though still superhuman) brood. textbook of astronomy in Europe during the last ["Results of the Astronomical Observations 35 years of the 18th century; in the latter work made.. .at the Cape of Good Hope," p. 41 5.1 Laande describes Kepler's derivation of the laws Herschel's suggestion was greeted with enthu- in moderate detail, but does not number them. siasm, and when, the following year, William Lassell And in contrast to Robert Small, he does not claim and George Bond independently discovered an these laws to be purely empirical or the result of an eighth satellite of Saturn, Lassell proposed to name .application of Baconian method." it Hyperion, and Bond agreed. This system and Editor's Note: Curtis Wilson, Professor Emeritus the now revived suggestion by Kepler and Marius at St. John's College, Annapolis, Maryland, has for Jupiter quickly beca:~: the convention for narn- written extensively about the history of celestial ing the satellites of the superior planets. mechanics from Kepler through the 19th century. Editor's note: This essay was originally posted His papers dealing with the early period are col- on HASTRO, Steve McCluskey's history of as- lected in Astronomy from Kepler to Newton, tronomy electronic discussion group. It is printed Variorum Reprints, 1989. He is an editor of Vol- here by permission of the author. 12 ume 2 of the WU's General History ofhtronomy. HAD Dues Tucson Meeting Invoices for 1995 HAD dues are scheduled to Our "annual" meeting will be held 7-9 Janu- be mailed by the AAS office at the end of Septem- ary 1995 in conjunction with the AAS meeting in ber. However, the mails do go awry. If you have Tucson. In addition to the sessions of contributed not received your invoice by the beginning of No- papers, there will be a public lecture and a pair of vember, please contact Sharon Savoy via e-mail at special sessions, co-sponsored by the AAS Educa- [email protected] or fax at 202-588-135 1. Q tion Officer and the Working Group onAstronomy Education, devoted to "Teaching Astronomy HAD Elections Through History." The schedule is a follows: Saturday, 7 January Preparatory to the upcoming elections, the 7:OO- 8:00 p.m. Public talk by E. C. Krupp on HAD Nominating committee, John Lankford, Native American astronomies. chair,' Dorrit Hoffleit and Von Del Chamberlain, Sunday, 8 January has nominated the following slate of candidates: 1:00- 2:30 p.m. HAD I: Contributed papers Chair 3:OO- 500 p.m. HAD 11: Specid Session 1 Woodruff T. Sullivan Monday, 9 January Vice Chair 10:OO-11:30 a.m. HAD 111: Special Session 2 David H. DeVorkin 1:OO- 2:00 p.m. Annual business meeting Michael Zeilik 2:OO- 3:30 p.m. HAD 111: Contributed papers Committee (two positions) Special Session 1 (HAD 11) bears the title Robert A. McCutcheon "Teaching Astronomical History: Past, Present and Richard L. Walker Future." It will consist of invited papers by Rich- Barbara L. Welther ard Berendzen, David DeVorkin, Barbara Becker, Thomas R. W~lliams and a speaker with whom we are negotiating. in accordance with the by-laws, further nomi- Specia! Session 2 (WiD 111) is dev~tcdto "The nations by petition must be sponsored by 10% of Use of History in Astronomy Education." It will the membership: 21 members. Nominees for Chair feature an invited paper by &en Gingerich and a and Vice Chair must be Full Members of HAD panel discussion, with audience participation. (i.e., members of the AAS). Nominees for the Com- Members of the panel will include the speakers mittee may be either Full or Affiliate Members of from HAD 11, plus a representative from a pub- HAD. Petitions should be mailed to LeRoy lisher of astronomy textbooks. Doggett, Nautical Almanac Office, U. S. Naval Abstracts for papers are due at the AAS office Observatory, Washington, DC 20392. They must by 21 October. Please note that the first session of be received by 3 1 October. contributed papers is on Sunday. If you are giving Ballots, with biographical information on the a contributed paper and have a strong preference candidates, will be mailed to members by 8 No- for one of the sessions, please speci+ it on the vember. They must be returned to the Secretary/ abstract. Otherwise your paper will be scheduled Treasurer by 27 December. As specified in the by- according to topic. fr laws, "A plurality of all votes cast shall be sufficient for election, except that the two nominees receiv- FSU Journal Fund ing the largest number of votes for Committee A year ago, HAD'S International Relations Member shall be declared elected. In case of tie, committee eitablished a fund to purchase sub- the Members present at the annual meeting shall scriptions to the joumifir the Hirtory ofhhonomy choose by ballot among the tied candidates." Can- for institutions in the Former Soviet Union. With didates will be informed of the results of the elec- a small donation you can make a significant con- tions by 2 January. Results will be announced at tribution to scholarship in the FSU. Please send a our annual business meeting on 9 January, when check payable to the Historid Astronomy Divi- the new officers will begin their two-year terms. sion, with a designation to the FSU Journal Fund, Of course, if you can't come to the meeting, there to LeRoy Doggett, Nautical Almanac Office, U. S. is your February Et4D News. Q Naval Observatory, Washington, DC 20392. Report from The Hague Report from The Vatican Steven J. Dick Rolf Sinclair The International Astronomical Union held "The Inspiration ofAstronomid Phenomena" its triennial General Assembly in The Hague, The was the theme of a meeting held at the Vatican Netherlands, August 17-25. It was an unusual Observatory at Castel Gandolfo, June 27-July 2, meeting both because of a new program format 1994. The meeting was frankly an experiment, to and a general reorganization of Commissions. look at the ways in which mankind has been fasci- Despite early fears, Commission 41 (History of nated by such phenomena, and how that fascina- Astronomy) emerged intact. What follows are only tion has been expressed through the ages. the history highlights from an extremely diverse The eighty attendees ranged from astronomers meeting. through historians and anthropologists to artists At the opening ceremony, Adriaan Blaauw pre- and musicians, students to senior researchers. All sented Queen Beatrix with his just-completed His- had a strong interest in one aspect or another of toy of the L4 U: The Birth andFirst Half-Centu y of the main theme. It was this common interest that the InternationalAstronomical Union, demonstrat- connected such diverse experiences, and that led ing that history is the highest and most elegant to many contacts, both formal and informal, dur- token of appreciation for royal attendance. This ing the meeting, and gave a common ground for meeting marked the 75th anniversary of the Union. discussion bounded by the reality of astronomy. It not only occasioned Blaauw's volume, but an No single recipe or rule emerged that would bridge entire morning session devoted to the history of perceived gaps between sciences and humanities; the IAU. rather, the result was a better appreciation of the During the anniversary session Blaauw pre- diversity of human response to the skies, and a sented a paper on some difficult episodes in the better sense of the importance of including astro- early history of the Union, including efforts to nomical phenomena in any study of man's culture make the Union truly international in the wake of and history. World War I. Other speakers included David The setting of the meeting, an isolated confer- DeVorkin, S. Dumont and M. J. Martres, Alex- ence center overlooking Lago Albano across from ander Gurshtein, Owen Gingerich, Woodruff Caste1 Gandolfo, helped develop a spirit of collegi- Sullivan, Barbara Welther, and Suzanne Dtbarbat. ality. One day was spent on a tour of the Vatican The session was attended by at least five past Gen- City gardens, a visit to some of the gems of the eral Secretaries of the IAU. Vatican Museums, and a tour of the Papal Library The afiernoon session was devoted to various and Archives that gave those who wished the op- history projects around the world, and other works portunity to plan return research visits. The Chi- in progress. Many of the papers were by astrono- cago artist John David Mooney created several mers who are devoting considerable efforts to his- works of art especially for the meeting, and gave torical studies. It is regrettable, however, that few out two memorable shirts of his own design. A professional historians were able to attend. "Proceedings" will be published in two parts, di- A good part of the meeting was taken up with viding the papers dealing principally with art from the proposed restructuring of the IAU, and the those on other subjects. The Vatican Observatory Executive Committee proposal that Commission is to be thanked for making the meeting ~ossible 41 become part of an "Interdisciplinary Division" and for its many thoughtful acts of hospitality. i? with Commissions 5 1 (Bioastronomy) and 14 (Atomic and Molecular Data). Since our Com- will consider the matter over the next few months. mission seems to be unique in being related to all The new officers of the Commission are other Commissions, a resolution was adopted re- S. M. R. Ansari (India), President, and S. J. Dick questing that commission 4 1 be directly affiliated (USA), Vice-President. New members of the Or- with the EC, rather than become part of another ganizing Committee are S. Dtbarbat (France), Division. This was rejected with the suggestion A. Gurshtein (Russia), M. Jano (Japan), D. King that Commission 41 might find a "center of grav- (Germany) and J. North (UK). The next meeting ity" in one of the Divisions. Officers and members of the IAU will be held in Japan in 1997. $r