J. Cassini
Contents
J. Cassini
(discontinued IAU name; formerly J. J. Cassini)
Lat: 73°N, Long: 20°W, Diam: , Depth: km, Rükl: 3 | |
Right: North-up aerial view from Lunar Orbiter IV-140H. In this view, 70 km [/Philolaus Philolaus] is on the left and 50 km [/Anaxagoras Anaxagoras] on the right. The crater straddling the bottom margin is Philolaus G (seems to be unnamed on the LROC Act-React Quick Map), while the larger of the two little craters in the upper right corner is [/Goldschmidt Goldschmidt] D. The [/Blagg%20and%20M%C3%BCller Blagg and Müller] position for what they called J. J. Cassini plots in the center of the valley. In the present IAU interpretation (where J. J. Cassini is no longer recognized) the west wall of the valley is regarded as a part of the east rim of the 91 km Philolaus D, while the valley itself, and the hills forming its east wall (which look like they might be remnants of the rim of a larger crater centered at roughly the same location), are unnamed.
Table of Contents
[#J. Cassini J. Cassini]
[#J. Cassini-Images Images]
[#J. Cassini-Maps Maps]
[#J. Cassini-Description Description]
[#J. Cassini-Description: Elger Description: Elger]
[#J. Cassini-Additional Information Additional Information]
[#J. Cassini-Nomenclature Nomenclature]
[#J. Cassini-LPOD Articles LPOD Articles]
[#J. Cassini-Bibliography Bibliography]
Images
LPOD Photo Gallery Lunar Orbiter Images
Maps
([/LAC%20zone LAC zone] 3A3) USGS Digital Atlas PDF
Description
Description: Elger
([/IAU%20Directions IAU Directions]) North of [/Fontenelle Fontinelle], extending towards [/Goldschmidt Goldschmidt] and the limb, Schroter discovered a very wide irregular valley which he named "J.J. Cassini." It is really nothing more than a great plain bounded by ridges. At 9 h. October 15, 1888, when [/Philolaus Philolaus] was on the morning terminator, I had a fine view of it, and, as regards its general shape, found that it agreed very closely with Schroter's drawing.
Additional Information
- See Plates A12 and A13 from the [/Consolidated%20Lunar%20Atlas Consolidated Lunar Atlas] for something similar to Elger's view on October 15, 1888.
Nomenclature
- Named for Jacques Cassini (1677-1756); son of [/Cassini G. D. Cassini] (founder of a dynasty of famous French astronomers, prominent at the Paris Observatory).
- As indicated by Elger, the name J.J. Cassini (actually "Jo. Jac. Cassini") was introduced by [/Johann%20Schr%C3%B6ter Johann Schröter] as illustrated in Plate 61 from Volume 2 of his book. Schröter's north-down drawing is reproduced below with most likely equivalent modern names superimposed (the text would have to be consulted to determine the significance of the dark shadow, and hence the identity, of the feature labeled "Anaxagoras/[/Poncelet Poncelet]?"):
- Some of these are new names added by Schröter. Others are ones from [/Riccioli Riccioli], which Schröter has identified differently from later observers, like [/Beer%20and%20M%C3%A4dler Beer and Mädler], who had more influence on the modern nomenclature (the drawing of the north polar region in Riccioli's map is so ambiguous there is no reason to think one set of "identifications" is better than any other). With the exception of [/Fontenelle Fontenelle] and J.J. Cassini, Schröter's other suggestions shown here were used elsewhere.
- The name introduced by Schröter was part of the original IAU nomenclature of [/Blagg%20and%20M%C3%BCller Blagg and Müller] (1935), where it had two [/satellite%20feature satellite] craters.
- Gerard [/Kuiper Kuiper] thought the second "J" was superfluous and shortened the name to J. Cassini in [/PLA%20Table%20III 1961].
- Shortly thereafter, that feature was deleted from the IAU nomenclature by Arthur et. al in preparing their [/Rectified%20Lunar%20Atlas Rectified Lunar Atlas] and [/System%20of%20Lunar%20Craters System of Lunar Craters] ([/IAU%20Transactions%20XIIB IAU Transactions XIIB], 1964). Apparently they felt this was one of those formations not "worthy" of a name. The commemoration of J. Cassini was “moved” ([/Whitaker Whitaker], p. 235) to the better-known crater [/Cassini Cassini] in the eastern hemisphere (previously honoring his father, G. D. Cassini, alone). - JimMosher JimMosher
- According to Schafarik (1877), the "J. J." in Schröter's name stood for "John James", although this Cassini is only rarely referred to as "J. J.". Schafarik's initial reference to J.J. Cassini being located in the region of Riccioli's [/Meton Meton] and [/Euctemon Euctemon] is puzzling, since according to [/Whitaker Whitaker] Riccioli's [/Meton Meton] and [/Euctemon Euctemon] were the same as the present ones (and they are in the eastern hemisphere). Elsewhere, Schafarik is clearly talking about the present feature. - JimMosher JimMosher
LPOD Articles
Bibliography
- Schafarik, A. (1877). On the Lunar Valley J. J. Cassini of Schröter. Astronomical Register Vol. 15, pp. 263-8. (Is this Bohemian astronomer related to the Vojtěch [/Safarik Safarik] for whom a crater is named??)
This page has been edited 1 times. The last modification was made by - tychocrater tychocrater on Jun 13, 2009 3:24 pm - afx4u2