Quad Maps

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Lunar Designations and Positions

(glossary entry)


Description

A series of four large charts known as Lunar Designations and Positions plotting the names and locations of features on the nearside of the Moon, were published by the University of Arizona in the late 1960. Each quadrant (I, II, III, and IV) is a mosaic of eleven smaller sheets that were published as part of the Lunar and Planetary Laboratory's System of Lunar Craters.

Additional Information

  • These maps were intended primarily to illustrate a major revision of the IAU nomenclature undertaken by the LPL and sanctioned by the IAU in 1964 and 1967.
  • The positions and diameters of the features (at least the craters) are based on new measurements made for the System of Lunar Craters.
  • In addition to the IAU-named and lettered craters the maps show the size and positions of all detectable unnamed craters greater than 3.5 km in diameter. These all had numbers in the accompanying System of Lunar Craters list. The maps also show and name many other features not printed in the list. These include Greek-lettered peaks, Roman-numeraled rilles, and unnamed scarps. Many of these map-only names also represent additions to or changes in the previous IAU nomeclature, and whether they were intended to be included in the IAU-approved changes is not entirely clear.
  • Although the LPL list was maintained on computer punch-cards, the published maps were hand-drafted by Alice Agneiray using ellipse templates to accurately represent the features as seen from Earth at zero libration.
  • The small Quad Sheets were bound in the volumes of the Communications of the Lunar & Planetary Laboratory by means of which the System of Lunar Craters was distributed.
  • The small Quad Sheets are numbered according to a system developed for the Photographic Lunar Atlas.
  • As the quadrants of the System of Lunar Craters were released, each was subsequently followed by a corresponding large quadrant map, printed separately as a map of "Lunar Designations and Positions". In 1969, revised versions of the large maps were prepared and sold, at first by the University of Arizona Press, and later by Sky and Telescope magazine (which refers to them as Lunar Quadrant Maps).
  • The original quad maps are mentioned in D.W.G. Arthur's 1964 presentation to the IAU (IAU Transactions XIIB), where they are called Lunar and Planetary Designations maps, and referred to as "two-color maps". Everywhere else (aside from in Sky and Telescope) they are called Lunar Designations and Positions maps.
  • Exact publication dates for Lunar Designations and Positions maps of Quadrants II-IV are listed in the Lunar Cartographic Bibliography of the IAU's 1967 Reports on Astronomy. They seemed to have appeared two to four months after the Communications of the Lunar & Planetary Laboratory issue containing the corresponding installment of the System of Lunar Craters. The explanatory text accompanying quadrants I and 3 are in English, while that for the remaining Quadrants is French (see USGS catalog listing). An entry in the catalog to the Clyde Tombaugh papers indicates that the size of the original series was 58x68 cm.
  • The large combined Quad Maps (at least the 1969 series) differ from the smaller sheets in that the mare areas are indicated by a shaded background. The earlier Lunar Designations and Positions maps may also have differed from the smaller map sheets in that they sometimes incorporated last-minute changes made after the corresponding catalog had been published. For example, according to Chuck Wood, the Quad II Catalog (published in LPL Communications 40) mentions that the Quad I Lunar Designations and Positions map includes new names from the Rectified Lunar Atlas that were developed too late to be incorporated in the Quad I catalog.
  • The only internet access seems to be to the original 44 smaller map sheets, fax-quality copies of which were placed on-line by GLR member Charlie Kapral who used them for plotting suspected lunar dome positions. Those maps may be viewed here. Charlie's index map preserves the original system of chart numbering. Newer, and much clearer, scans of a few of the small map sheets can be found on the System of Lunar Craters page.


LPOD Articles

Sheets and Quads
Quad 3

Bibliography