Antonín Rükl: Atlas of the Moon



This series of careful maps of the Moon's nearside and libration zones, created by the former director of the Prague Planetarium, is widely regarded by amateur astronomers as the indispensable observing guide to lunar features. Although this is a private publication, Rükl has generally striven to adhere to the IAU nomenclature as closely as possible.

Additional Information

  • Rükl uses the traditional system of labeling satellite features by their letters only, placed on the side towards the parent feature after which it is named. In recent years, printed maps of this sort have been somewhat supplanted by electronic products which are generally more flexible, and can be more easily updated to reflect changes in the official nomenclature and avoid inadvertent errors. Rükl's maps do not show all IAU-approved satellite feature names (at the time the maps were being prepared, the IAU did not maintain an official list of lettered craters), and in a very few cases his labels are erroneous or ambiguous.
  • Reproductions of Rükl's maps can be found on a number of websites. The current authorized edition of Rükl's Atlas of the Moon is said to be available from Sky Publishing, although it is reportedly out-of-stock.
  • The following image compares a detail from Rükl's Atlas (Sheet 22, right) with the comparable area as seen in the newer Lunar Orbiter-based IAU/USGS on-line Digital Atlas (Sheet 41, left, much reduced):
    • LAC41_LO-Rukl22_comparison.jpg
      Rükl's Atlas map (right) compared to more modern IAU photographic atlas (left)
    • Note that Rükl's map consists essentially of a line-and-shadow rendering of the Lunar Orbiter imagery augmented with some low relief and albedo features interpreted from images with higher and lower sun angle. Not only is the nomenclature not always complete or reliable, but in the process of artistic interpretation certain features are emphasized and others lost. For example, a little to the left of center, one small crater is shown on the floor of Palus Putredinis, but two more prominent ones to its north are omitted (note: this is the officially unnamed pair of bowl-shaped craters immediately west of NASA's Hill 305, also known as the southern part of the Fresnel Ridge).
  • The maps in the Hamlyn Atlas were preceded by a set of six Maps of the Lunar Hemispheres, published in 1972, which covered the entire Moon in orthographic views, but in less detail.
  • Before that, Rükl published a south-up "Skeleton Map of the Moon" at a scale of 1:6000000 (roughly 22.5 in diameter) which was distributed with Kopal's Photographic Atlas of the Moon (1965). This map labels most primary and selected satellite features. It uses the pre-Latinized names ("Alpine Valley", etc.), and is numbered in the corner with quadrant numbers, although more detailed maps for the quadrants do not seem to have been distributed with it. - JimMosher JimMosher
  • Rükl also participated in the production of the new Sky & Telescope Field Map of the Moon which is intended for use at the telescope, and shows the Moon's nearside in quadrants.
  • Antonín Rükl died on 12 July 2016 - he was 83.- JohnMoore2 JohnMoore2
    • A-Rukl.jpg
    • Credit: Observatory and Planetarium of Milan, Rastislav Štefánik in Hlohovec.

Rükl's Zone System

  • In the Hamlyn Atlas, Rükl divided the Moon's nearside at zero libration into 76 equal-sized and non-overlapping rectangles. From north to south there are eight rows of maps. The rows vary in length from seven maps per row at the north and south poles, to nine maps per row immediately "below" the polar rows, and eleven maps per row in the remaining four rows. The rectangular maps are assigned consecutive Arabic numbers from "1" to "76". There appear to be eight small areas that fall outside the formally defined rectangles, and which are depicted as extensions of the horizontally adjacent zones. In addition to the 76 orthographically mapped rectangles, Rükl drew eight maps of the libration zones with special projections. The libration zones maps are identified by Roman numerals starting with "I" in the NNW and continuing clockwise through "VIII" in the WNW.
  • The Rükl numbering system is illustrated by clickable maps on the Planet Moon website of the Lunar Section of the U.A.I. (the Italian national amateur astronomy organization) and on Akkana Peck's Hitchhiker's Guide to the Moon. An index to major IAU-named craters in each of the 76 Rükl zones can also be found in Antonio Cidadão's interactive Moon-"Light" Atlas.

The other Rukl atlas

  • There is also an experimental Rükl zone based index to the features described on the present Wiki. In this experimental atlas, each one of the 76 of Rukl's individual charts has an additional list of unofficially named and nicknamed formations! All of the historical disallowed names from van Langren, Hevelius, and Riccioli are also included! - DannyCaes DannyCaes Jul 15, 2016

LPOD Articles

What's a Rukl?
A Wallfull of Rukl


  • Rükl, Antonín. Maps of lunar hemispheres. Giving the views of the lunar globe from six cardinal directions in space. With a foreword by Zdeněk Kopal. Dordrecht, Reidel [1972]. (the Polish edition can be viewed on the IPCD website)
  • Rükl, Antonín. Atlas of the moon edited by T.W. Rackham. London : Hamlyn, 1991, c1990.

This page has been edited 19 times. The last modification was made by - DannyCaes DannyCaes on Jul 15, 2016 11:58 am - mgx1