IAU Transactions XVA

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TRANSACTIONS OF THE IAU : VOLUME XVA (REPORTS)
(the following is excerpted from the book published by D. Reidel, 1973)

REPORTS ON ASTRONOMY (1973)



Edited by
CORNELIS DE JAGER
General Secretary of the Union

from pp. 203-206

17. THE MOON (LA LUNE)


PRESIDENT: A. Dollfus.
VICE-PRESIDENTS: G. P. Kuiper, B. Levin.
ORGANIZING COMMITTEE: A. Anders, G. Fielder, D. Menzel, P. Millman, T. Weimer.

The President of Commission 17 "The Moon", M. Minnaert, died soon after his election at the IAU 1970 general assembly. His fundamental contribution to lunar photometry and nomenclature is well remembered. A. Dollfus, former President of the Commission, was invited by the IAU Executive Committee to serve again as President for the period 1970-1973.

Other members, whose deaths are regretted, are W. J. Eckert and C. B. Watts; and among the former members V. G. Fesenkov and N. P. Barabashov.

The period 1970-1973 corresponded to the apex and the completion of the U.S. Apollo manned lunar exploration program, and to the development of the U.S.S.R. Luna automatic lunar exploration program. It has been an unparallelled period in the annals of lunar studies. The major task of the IAU Commission has been to respond to new requirements by an adaptation of the international structures of science. This has been effected by the organization and guidance, within the EAU and other international scientific unions, of suitable working groups, a working party and an interunion commission. The groups set up are:

IAU Working Group "Lunar Nomenclature" (Chairman D. H. Menzel).

IAU Working Group "Figure, mouvements et positions observées de la Lune" (Chairman Th. Weimer).

IAU Working Group "Geology and Geophysics of the Moon" (Chairman G. Fielder).

IAU-COSPAR-IUGG Working Party "Lunar Laser Ranging Experiments" (Chairman C. O. Alley).

ICSU "Inter-Union Commission for Lunar Studies" (IUCM-CIUL) Affiliated to IAU-URSIIUGG-IUGS-COSPAR, (Chairman A. Dollfus).

The individual activities of these groups are outlined below.

The coming period 1973-1976 will be dominated by the USSR Luna automated lunar exploration program, the U.S. post-Apollo lunar science program, and the extensive exploitation of the vast quantity of lunar observational data already acquired.

The international groups listed above are preparing their individual contributions to this fundamental task.


INTER-UNION COMMISSION FOR LUNAR STUDIES (IUCM-CIUL)


In 1965, the former President of IAU Commission 17, Prof. Menzel, in view of the proposed NASA-Apollo manned lunar landing program, predicted that future studies of the Moon will involve more diversified fields than astronomy, namely, space sciences, geology, geophysics. He proposed to study the need for organizing a coordinating body grouping scientists representing the different disciplines involved.

During the first part of his mandate (1967-1970), the following President (A. Dollfus) re-investigated possibilities with a view to the urgent pressure triggered by the large amount of scientific results outcoming from the first manned landing operation (Apollo 11). The International Committee of Scientific Unions (ICSU) decided, during their l3th General Assembly (September 1970), to create a "Inter- Union Cornmissioli for Lunar Studies - Commission Inter- Union pour l'Etude de la Lune" (IUCM-CIUL).

This group of representatives of the Scientific Unions of ICSU involved in lunar studies operate on three ways: an advisory panel - a coordinating body - a channel through the Scientific Unions. The Unions and members are the following:

IAU (Astronomy): A. Dollfus (Chairman) - E. Anders.
IUGG (Geophysics): S. K. Runcorn, G. D. Garland (Alternate).
IUGS (Geology): W. Von Engelhardt - S. Van der Heide (Alternate).
URSI (Radio-Science): M. P. Misme - T. Hagfors and V. S. Troitsky (Alternates).
COSPAR (Space Research): H. Mazursky - K. P. Florensky (Alternate).

The parent Union is the International Astronomical Union. The Chairman is A. Dollfus (Observatoire de Paris, 92 Meudon, France). The Secretary is J. E. Guest (University of London Observatory, 33/35 Dawns Lane, London NW7 4SD, England).

The Constitution meeting was held in Paris on 24 May 1971. The first formal session was held in Paris on 15 November 1971. An informal session was organized in Houston (Texas) on 12 January 1972. A general assembly met on 28-29 Nov. 1972.

One of the first actions of IUCM-CIUL was to react officially at the NASA's announcement concerning a possible cancellation of the two last already scheduled manned missions to the Moon - Apollos 16 and 17. The Chairman of IUCM-CIUL transmitted to President Nixon, through IAU's General Secretary, the statements and resolutions adopted by IAU during the past years to emphasize the importance of lunar exploration for the development of science in the present conjuncture.

The following items have been given active consideration by IUCM-CIUL:

Lunar nomenclature: The need for a proper nomenclature to lunar features of smaller scale than those already designated in the IAU system (worked out for the earth-based telescopic observations), was reviewed through the different disciplines represented within IUCM-CIUL. It was agreed that the responsibility for this task should continue to be the existing IAU Working Group, and the extension of its responsibility to the smaller features was fostered by the appointment of Dr Mazursky to this group. IUCM elaborated also the contacts with the United-Nations Working Group "Names of Extraterrestrial topographic features" under the chairmanship of Dr Komkov.

Lunar coordinates: The Inter-Union was asked to consider the problem of a unified lunar coordinates system. Reports and discussions on earth-based, spacecraft and other results concluded that, at the present time, it is premature to accept a system of coordinates derived by one method. A final system should be based on the Moon's center of mass and the principal axis of inertia. A list of about 200 craters to be used as reference locations for measurements should be agreed between workers from different groups. This list should include sufficient craters within the areas covered by Apollo metric photography to satisfy those workers involved in photogrammetric analysis. The sub-group of the IAU-Working Group "Figure, mouvements et positions observées de la Lune" is working along this line.

Panel of Scientific Priorities: IUCM-CIUL act as an advisatory group emanating from the different disciplines involved in lunar science to localize the lunar studies in the scientific priorities requested by the Panel of ICSU.


WORKING GROUP ON LUNAR NOMENCLATURE


Members: D. H. Menzel (Chairman), B. Levin, A. Dollfus, H. Mazursky.

The task assigned to the former Working Group (1967-70) was the designation of the major craters of the farside of the Moon. After completion of this work and its official endorsements at the last 1970 IAU General Assembly, the task of the Group was re-directed towards the nomenclature problem of the smallest features of the lunar surface.

Apparently the current system of nomenclature worked out at the time of lunar telescopic observations and improved in successive steps by IAU fitted well the needs for the lunar studies at the groundbased telescopic scale. But clearly the new needs of the space exploration reaching resolving power of the order of 100 times smaller than the best telescopic observations (10° more pixels), and a fortiori of the direct exploration needing mineralogic sizes scale, requires more than a crude extension of the existing system. The new NASA mapping program at a scale 1:250000 opens the problem in practical terms.

Due to the great activity of W.G. developed with the cooperative advices of the Inter Union IUCM-CIUL, the problem is moving fast in the period of writing the present report (Jan. 73). Accordingly, the following adoptation of an Interim Report (Dec. 11, 1972) by the Chairman D. H. Menzel has the character of a progress report:

"The current system of lunar nomenclature, nearside only, was developed by Mädler between 1830 and 1837. He established the system of naming the larger craters and assigning capital Latin letters to surrounding, smaller, `satellite' craters. Many maps have been prepared and published since Mädler 's day, with increasing detail. Between 1921 and 1935, Blagg and Müller, under auspices of the IAU, prepared an extensive review of the existing maps. At the same time, they arbitrarily assigned letters to many small craters, leaving numerous craters of intermediate size undesignated. The Lunar and Planetary Laboratory of the University of Arizona, during the past fifteen years or so, has continued with an excellent and critical study of the problem. These studies led to the production of an Atlas and Gazetteer of the Near-Side of the Moon, published in 1971 under the authority of the National Aeronautics and Space Administration, as NASA SP-241. This excellent volume, based on photographs taken with lunar Orbiters rather than on ground-based photographs or hand-drawn maps, contains the best summary, to date, of lunar nomenclature for the near side of the Moon.

"Of the 6050 designated features on the Moon's near side, approximately 700 are listed as primary objects and the remaining as satellites. Capital Roman letters were used for craters, valleys, and other depressions; lower case Greek letters were used for hills, mountains, and other 'eminences'. This traditional system is cumbersome, and almost impossible to extend to smaller features.

"There is an urgent need for new decisions. NASA is currently planning to start a new series of lunar maps, which are likely to be standard for a long time to come. These maps, drawn on a scale of 1:250000 will require about 200 in all. The first objective, which will start in March 1973, will be the production of approximately 50 such maps, covering primarily the equatorial zones extensively photographed by the lunar Apollo missions. A sizeable number of these large-scale maps will not contain a single named feature, particularly for the far side. And, for the near side, a large number will have as its primary feature only one of the lettered craters, such as Picard Y, and so on.

"NASA advises that they would like to name each sheet for a principal named feature. They feel that duplication of features, such as having one chart named Picard, say, and another Picard Y could be extremely confusing. Accordingly, NASA has officially requested our Working Group to proceed with the revision we have proposed for craters on the near side, and continue with supplying additional names for the far side. NASA has indicated its approval and support of IAU authority in this matter.

"Accordingly the Chairman is proceeding along lines followed for the preliminary naming of the far side, contacting international groups for suggestions of names, with emphasis on persons other than physical scientists, who have dominated in prior selections.

"Our list will include, however, a few distinguished scientists, primarily astronomers, who have died since the last general assembly. It will also include a number of physical scientists whose names were omitted earlier because of the similarity in sound to others already approved. Thus Born had not been included because of its similarity to Bohr; Rutherford because of its similarity to Rutherfurd; Lawrence because of its similarity to Lorentz. We have since determined that these 'sound-alikes' are not unacceptable.

"The Working Group, with the help of a sub-committee of the cartographers, also considered the problem of nomenclature of smaller features, perhaps down to diameters of less than 100 meters. It was suggested that `given names', such as John, Mary, Edward, Nikolai, Courtney, and the like, would provide satisfactory names. The features themselves will generally be too small for identification on anything other than photographs showing the area, perhaps with photographs of intermediate scale to bridge the gap between the small-scale photographs and existing maps. The suggestion proposed by some that the latitude and longitude of an object, large or small, be translated into a literal code, is not satisfactory at least at the present time. We do not have the system of lunar coordinates adequately defined to make such alpha-numeric systems practical.

"There is one final point to emphasize concerning our selection of names. We shall continue to exclude all political figures, national heroes, religious figures, and modern philosophers. Ancient philosophers and various legendary figures will be accepted, however."

The subsequent phases of the work following this interim-report will be presented at the general Assembly, Sydney, Aug. 1973.