Montes Leibnitz

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Montes Leibnitz

(discontinued IAU name; formerly Leibnitz Mountains)

Lat: 78-90° S, Long: 90° E, Length: 370 km, Height: km, Rükl 73

external image Moon_20060703_1956UT_0012_wl_10NW2B_IRP_Det_T.jpg
Helmut Groell The "Leibnitz Beta" of Whitaker (1954, see below) is labeled. This appears to have been "Leibnitz e" in Schröter's original drawing of the range.

Images

A-B-C-D-E-of-MontesLeibnitz.jpg
Top and Botttom: LROC views of the mountains A, B, C, D and E as seen by Schröter (see also images in Schröter's Observations section below). - JohnMoore2


Maps

(LAC zone LAC 144D1)

Description

Suspected mountain range near or on the moon's south pole (the moon's southern limb).

Description: Elger

(IAU Directions) LEIBNITZ MOUNTAINS.-- On the S. limb extending E. from S. lat. 80 deg. beyond the Pole on to the Fourth Quadrant. Perhaps the loftiest range on the limb. Madler's measures give more than 27,000 feet as the height of one peak, and there are several others nearly as high.

Additional Information

  • Could this be the most southern part of the giant South Pole-Aitken basin on the moon's far side? (partially visible during favourable librations). Yes. - tychocrater Feb 9, 2009
  • According to Neison "This magnificent range of mountains was discovered and measured by Cassini in 1724," and re-discovered by Schröter (see below).
  • This region was satisfactorily photographed during the fly-by of the Galileo probe and the orbital mission of the Clementine probe in 1994.


Nomenclature

  • Named for Gottfried Wilhelm Leibnitz (1646 - 1716), a German mathematician (see Leibnitz, the modern name for an unrelated farside crater).
  • According to Whitaker (p. 218), this name was introduced by Johann Schröter.
  • As noted by Webb in 1858, Beer and Mädler, who were generally rather dismissive of Schröter's work, do not seem to have understood his description of either the Leibnitz Mountains or the Doerfels (to their west), interchanging the names and saying Schröter's intentions were unclear. Since Schröter's intentions were in fact quite clear, Webb rejected Beer and Mädler's name switch.
  • Neison, 1876 followed Webb in retaining Schröter's names for the ranges seen on the two sides of the pole, and also assigned Greek-letter designations to a number of the Leibnitz peaks, quite different from Schröter's initial set of letters.
  • Leibnitz Mountains was part of the original IAU nomenclature of Blagg and Müller (1935) which also included six Greek-lettered peaks, attempting to follow Neison's positions and lettering.
  • Ewen Whitaker may have somewhat modified and rearranged these names in an influential 1954 article. The most popular of Whitaker's names, still in informal use, is Leibnitz Beta, now used for a large and relatively flat-topped massif on whose slopes are the IAU named craters Scott M and Malapert E (see, for example, Spudis, et al. 2008). Whitaker believed he was merging the IAU’s original Leibnitz Beta and Kappa, although Neison regarded Kappa as a separate peak in another range.
  • The name was Latinized to Montes Leibnitz in IAU Transactions XIIB (1964). It was cancelled, along with Montes Sovietici and three others, in Menzel, 1971 as representing non-existent mountain chains.
  • The name Montes Leibnitz is still printed on some of the modern Moon maps, such as the Hallwag map.


Schröter's Observations

Johann Schröter, name-giver to the Leibnitz Mountains, was a meticulous observer who left careful records of his observations, including the date and time at which they were made, and such things as a record of the observed librations by means of noting how far Plato and Grimaldi were offset from the limb. The date and time makes it easy to reconstruct what he must have seen based on data on the shape of the Moon's surface returned by instruments on the Kaguya and LRO spacecraft.

In the case of the Leibnitz peaks, Schröter's initial observation was on December 2, 1789 at about 18:00 UT, at which time he saw four relatively prominent peaks along the Moon's limb. He called these Leibnitz a, b, d, and e (from west to east), noting that a straight line from Mare Nubium through Tycho crossed the limb at Leibnitz d (which he sometimes calls "Delta"). He also carefully recorded the width and spacing of the peaks (as well as their heights), and noted a small fifth peak, c, between b and d. This careful description unambiguously identifies the peaks as shown in the simulation at left below. This is "unrolled" into an aerial view in the final image, where the locations of the features producing the labeled peaks in the first two simulations is indicated relative to modern IAU-named features (represented by a gray-scale version of the topographic heights, white being high, and black low). The blue line is the theoretical limb, with most of the area above the line visible from Earth.

Dec 2 1789
Aerial View

external image Schroter_Leibnitz_peaks_1789Dec02_1800UT.JPG

external image Schroter_Leibnitz_peaks_1789Dec02_aerial.JPG

Schröter does not seem to have made a systematic study of this south polar region, which displays many other peaks at the limb at different librations. It is also interesting to note that although modern amateurs are found of looking at this portion of the Moon's limb with a strong southerly libration, the features Schröter named are those presented at near zero libration.

The correspondence of Schröter's December 2, 1789 Leibnitz Peaks (T. IV, Fig. 7) with Whitaker's 1954 nomenclature is as follows:
Schröter
Whitaker
a
M3
b
M1
d
Malapert Alpha
e
Leibnitz Beta


Note: the preceding was based entirely on a reading, by a person with little knowledge of German, of the verbal description in the on-line scan of Volume 1 of Schröter's book. The words refer to Fig. 7 in plate T. IV, in which Schröter illustrated these observations. Reproductions of that plate, and of the text of Volume 2, do not appear to be available on-line, however a scan of T. IV has recently been made available by Nigel Longshaw, and it confirms that the drawing, and its lettering, closely match the simulation (although rotated 180°). An examination of the following drawing in plate T. IV reveals that although the identification of the "a".."e" of Fig. 7 with Whitaker's named features is correct, Schröter attached little significance to the letters: in Fig. 8 of T. IV, the letters "a".."e" are used again, but placed in the opposite order. Therefore, the letters used to label individual peaks in Schröter's "Montes Leibnitii" (their designation in Fig. 7) should not to be taken as permanent names identifying specific features (as Whitaker's are), but only as convenient markers for use within the context of the image on which they appear. In Volume 2, Schröter appears to have made extensive observations of the polar cusps of lunar crescents (see Plates TLXV, TLXVI and TLXXIV), and may well have introduced additional, or different, nomenclature in connection with them. Schröter also appears to have traced the south polar limb profile, silhouetted against the solar disk, labeling the peaks he saw during an eclipse (TLXIII).- JimMosher

Neison's Observations

Neison explains the labeling of the south polar peaks in his 1876 book (pages 435-436 and map, later adopted by the IAU) in somewhat greater detail on pages 61-62 of the August 6, 1880 issue of the Selenographical Journal. For example, he describes the appearance of the double-peaked mountain he designated Leibnitz Alpha as seen on the limb on August 31, 1879. It is evident from this that the smaller part (Alpha1) is Whitaker's M4 and the larger part (Alpha2) is M5. Unfortunately, Neison fails to provide dates or times for his other observations, so his intent for the remaining names is less clear. From the descriptions of their horizontal extents it seems possible that Neison's Leibnitz Beta may be Whitaker's Malapert Alpha (although Neison's placement of Malapert to the west of the central meridian on his map is inconsistent with this), and Neison's Leibnitz Gamma may be Whitaker's Leibnitz Beta.

LPOD Articles


Bibliography