National Geographic : 1981 Nov
Members Forum SOLAR SYSTEM I am confused about Saturn's moons. The most recently discovered moon (before Voyager 1), Janus, was not shown in your article. Todd McComb Fort Wayne, Indiana Because of many recent discoveries, the number and names of Saturn's moons are indeed confus ing. Once a moon has been confirmed by more than one observationand its precise orbit deter mined, it is given a permanentnumber and name. Janus was an unofficial name given to the moon observed by A. Dollfus in 1966. Observations from Voyager now show two moons in that loca tion orbiting together; one of these is the moon known as Janus. How anything as flagrant as the one-tenth ratio of Jupiter to ol' Sol got by is hard to compre hend-more like one-thousandth. John Wensinger Santa Rosa, California NATIONAL GEOGRAPHIC was using diameter, not volume, in comparing sizes of planets or moons, as do most scientists. The diameter of Jupiteris 142,800 km and that of the sun is 1,400,000 km. If you want to know more about Voyager's ac complishments on its journey past Saturn and into the solar system, NATIONAL GEOGRAPHIC is the bible. Lee A. DuBridge President Emeritus California Institute of Technology, Pasadena UNITED STATES ARTICLES The Society is not national any more, it is inter national. Most of the time you only have one sto ry on the Good Old U.S.A. Roy Losh Utica, Ohio Why so many articles every month on America? Robin Watts Wahroonga, Australia We include a United States article in every issue, since most of our members live here and reader demand is high-evenfromforeign members.