bluuebunny/crossref_metadata_2025 huggingface dataset:
24. Commission des Parallaxes Stellaires et des Mouvements Propres
Authors: Mitchell M. S. A. , Adams M. M. , Alden  , Bianchi  , Curtis  , Davidson C. R. , de Sitter  , Fox  , Harper  , Jones  , Jordan  , Knox-Shaw  , Lee  , Lindblad  , Lockyer  , Luyten  , Miller  , Moffitt  , Nechvíle  , Russell  , Schlesinger  , Shapley  , Slocum  , Smart  , Van Maanen  , Van Rhijn  , Voûte
Published: July 2016

In November 1931 the President circulated a letter to the members of the Commission which in part was as follows:

In view of the fact that it is now over a quarter of a century since Schlesinger by photography began to determine trigonometric parallaxes by a long focus telescope, and fifteen years since Adams and Kohlschütter derived the first spectroscopic parallaxes, it would seem appropriate to take stock of our present position and to make plans for future development.

Will you be good enough, therefore, to furnish such statements concerning the following topics as are appropriate to the work of your observatory?
30. Commission des Vitesses Radiales Stellaires
Authors: Plaskett M. J. S. , Adams MM. , Campbell W. W. , Frost  , Hamy  , Harper  , Henroteau  , Jones  , Joy  , Moore  , Pearce  , Salet  , Sanford
Published: July 2016

The four years that have elapsed since the last meeting of the International Astronomical Union have witnessed steady progress in the determination of radial velocities, principally at the Mt Wilson Observatory, Pasadena, Cal., the Lick Observatory, Mt Hamilton, Cal., the Yerkes Observatory, Williams Bay, Wis., the Dominion Astrophysical Observatory, Victoria, B.C., the Observatory of the University of Michigan, Ann Arbor, Mich., and the Simeis Observatory in Russia. It will be useful, for the members of the Commission, to give a short summary of the radial velocity work completed and in progress since the last meeting.
33. Commission de la Statistique Stellaire
Authors: Van Rhijn M. P. J. , Baillaud MM. J. , Charlier  , Eddington  , Hertzsprung  , Hirayama S. , Lindblad  , Lundmark  , Luyten  , Malmquist  , Oort  , Pannekoek  , Russell  , Seares  , Stromberg  , Van Maanen
Published: July 2016

The following recommendations have been made:

1. That a catalogue of the fainter stars with known proper motions or at least a list of the authorities of the proper motion of the fainter stars should be published (Van Maanen).

2. That the parallax observers are requested to publish the basis of selection of the stars of their observing programme.
Commission 7. (Dynamical Astronomy.)
Authors: Strömgren E. , Roy Felix De
Published: July 2016

After having marked his agreement with Prof. de Sitter, when he stated in his report (p. 27) that at the present moment there do not appear to be any problems in dynamical astronomy requiring combined action and international co-operation, the Chairman briefly reviewed those problems in dynamical astronomy which have been studied in the past four years.

They include methods for the determination of orbits and their adaptation to the use of computing machines; multiple solutions in the problem of the determination of orbits; researches on the final state of dynamical systems with slowly varying parameters (e.g. with varying masses), applications, for instance, to the problem of tides; general dynamical problems of stability and recurrence; lunar theory (problems of convergence, non-uniformity of the rotation of the Earth); problems of perturbations (development of the perturbation function, the Trojan group and other asteroid problems, satellites); the restricted problem of three bodies (numerical investigations and their mathematical foundation, the problems of “sorts” and “groups” [“Klassen”]; analytical investigations on the non-existence of periodic solutions in the range of critical commensurabilities); regularization of the singularities of the problem of three bodies; special cases of the problems of 3 and n bodies; general mathematical theory of the existence of rotating figures of equilibrium; relativity—gravitation—light.
Commission 9. (Astronomical Instruments.)
Authors: Pluvinel M. le Comte de la Baume , Chrétien H.
Published: July 2016

The Commission discussed and adopted the President’s report and passed the following resolution for submission to the General Assembly:

“La Commission souhaite que l’on se mette d’accord pour définir des nombres caractéristiques pouvant représenter les qualités optiques des grands instruments.”
Commission 22. (Étoiles Filantes.)
Authors: Olivier  , De Roy M. F.
Published: July 2016

The Rev. T. E. R. Phillips submitted a proposal from Commission 16, suggesting that Commission 22 should take from them the subject of comets. After some discussion, in which it was pointed out that, on practical grounds, the methods of observation should outweigh any theoretical considerations in the matter, the following motion was moved by Prof. Öpik, seconded by Prof. Boothroyd, and carried:

“Commission 22 considers that it is not desirable that Comets should be joined to their subject.”
Commission 23. (Carte du Ciel.)
Authors: Esclangon M. , Hujer M. K.
Published: July 2016

M. le Président rend hommage à ceux de ses membres que la Commission a perdus depuis sa précédente réunion: son eminent Président Turner, le P. Hagen et M. Cosserat.

Il rend succinctement compte de l’état des travaux du Catalogue et de la Carte, et fait ressortir les notables progrès effectués depuis le dernier Rapport.
Commission 24. (Stellar Parallaxes and Proper Motions.)
Authors: Mitchell S. A. , Slocum F.
Published: July 2016

There were two meetings of the Commission. The first meeting was devoted to an informal discussion of programmes for parallax work. The second session was devoted to a discussion of systematic errors. The President gave a brief summary of the two latest determinations of the systematic errors of trigonometric parallaxes, by Schlesinger (parallaxes published to 1924) and by van Maanen (parallaxes to 1927). Both investigators had used the same basis of comparison, namely, the Mt Wilson spectroscopic parallaxes, and both had made the same fundamental assumption, namely, that the systematic errors of the spectroscopic parallaxes depending on right ascension were negligible.
Commission 28. (Nebulae and Stellar Clusters.)
Authors: Lundmark K. , Miller F. D.
Published: July 2016

Dr Lundmark called attention to the deaths of two members of the Commission, Miss Adelaide Ames and Father J. G. Hagen, and of a past member and former chairman, Dr G. Bigourdan, and outlined their contributions to the subject.

The secretary read a letter from the chairman, Dr Hubble, suggesting that the meeting be devoted primarily to informal discussion of relevant problems.

Dr Lundmark, as an introduction, read the recommendations adopted by the Commission in 1928. This was followed by the reading of the first part of the acting chairman’s report on the advance and present state of knowledge of the anagalactic nebulae.
Commission 29. (Stellar Classification.)
Authors: Russell H. N. , Beals C. S.
Published: July 2016

The Commission held two meetings and the time was taken up almost entirely in a discussion of stellar classification.

Dr J. S. Plaskett moved, seconded by Miss Payne, that a sub-committee be appointed to consider the classification of Wolf Rayet and related spectra.

The committee was appointed as follows: Miss C. H. Payne, Prof. H. H. Plaskett, Dr C. S. Beals, Chairman.

Dr W. S. Adams moved, seconded by Dr J. S. Plaskett, that a sub-committee be appointed to tabulate and bring up to date criteria of classification for both high and low dispersion at present in use throughout the stellar sequence.

The committee was appointed as follows: Miss A. J. Cannon, Dr O. Strave, Prof. H. H. Plaskett, Dr B. Lindblad, Dr W. S. Adams, Chairman.
Commission 31. (Bureau De l’Heure.)
Authors: Nörlund N. E. , Lambert M. A.
Published: July 2016

Après avoir rappelé le souvenir du Général Ferrie et de M. Bigourdan, décédés au cours de l’année, le Président met aux vœux l’élection du Vice-Président de la Commission, en remplacement du Général Ferrie. A l’unanimité le Général G. Perrier est élu et il est invité par le Président à prendre place au bureau.

Le Président fait connaître qu’il a examiné les comptes du B.I.H. pour les quatre dernières années et que les règlements ont été respectés:

Les dépenses se sont élevées.
11. Commission des Phénomènes Chromosphériques
Authors: d’Azambuja M. L. , Abetti MM. , Bosler  , Brunner  , Butler  , Lobo da Costa , Deslandres  , Donitch  , Evershed  , Haie  , Newbegin  , Newton  , Nicholson  , Pettit  , Rodés  , Royds  , Sotome  , Unsöld
Published: July 2016

Au cours des trois années 1932,1933 et 1934, les relevés et statistiques habituels des flocculi, des protubérances et de l’épaisseur de la chromosphère, ont été poursuivis et publiés régulièrement. Ils se répartissent de la manière suivante:
12. Commission de la Radiation Solaire et de la Spectroscopie Solaire
Authors: Abetti M. , Abbot MM. , Babcock  , Carrasco  , Carroll  , Chapman  , d’Azambuja  , Dingle  , Evershed  , Lyot  , Menzel  , Milne  , Minnaert  , Moore Mile C. E. , Pannekoek MM. , Pettit  , Plaskett H. H. , Russell  , Stetson  , Unsold  , Woolley
Published: July 2016

The majority of the members of the Commission have been good enough to send in full reports regarding subjects of interest to this Commission. Extracts from them relating to questions which may be the subject of useful discussion at the forthcoming meeting in Paris are given below; references to research undertaken during the last three years, particulars of which are readily available in recent astronomical publications, are omitted.
14. Commission des Étalons de Longueur d’onde et des Tables de Spectres Solaires
Authors: Fowler M. A. , Babcock MM. , Burns  , Fabry C. , Jackson C. V. , Kayser  , Meggers  , Nagaoka
Published: July 2016

The 1932 report of this Commission, and the report of the ensuing discussion, revealed an unsatisfactory position with regard to sources of the red line of cadmium which could be relied upon to give the adopted standard value for the wave-length 6438.4696 x 10−10 metre.

Dr Meggers has summarised the position very clearly in a recent paper on “ Interference Measurements in the Spectra of Noble Gases” (B.S.J. Research, 13, 293, 1934) and has expressed a strong preference for the specification of the Michelson lamp adopted in 1927 by the International Conference of Weights and Measures (see Trans I.A.U. 4, 58, 1932). He points out that the I.A.U. specification of 1925 is less restricted, inasmuch as it does not exclude high-frequency excitation and makes no mention of the volume or capillary bore of the tube, but requires that it must give interferences with differences of path of at least 200,000 waves. The last condition is considered objectionable on the ground that this is less than half of the theoretical or actual limit of the Michelson tube, and it is further considered that cadmium sources in which any such reduction in interference order occurs will certainly yield a different value for the primary standard.
18. Commission des Longitudes par Télégraphie Sans Fil
Authors: Perrier G. , Lambert M. A. , Bianchi MM. , Bowie  , Coculesco  , Lobo Da Costa , de Lemos  , Esclangon  , Fayet  , Fichot  , Hashimoto  , Iwanoff  , Jackson J. , Jeffers  , Jones  , Jouaust  , Kohlschütter E. , Krassowski  , Lambert A. , Lejay  , Moreau  , Niethammer  , Nörlund  , Nušl  , Plakidis  , Sampson  , Silva  , Sollenberger  , Stewart  , Stoyko  , Volta  , Watts  , Witkowski
Published: July 2016

Trois résolutions ont été adoptées par la 4e Assemblée générale de l’Union astronomique internationale, à Cambridge (Mass.) en 1932.

Elles se rapportaient à l’opération internationale des longitudes (réalisée en 1933) et avaient pour objet:

(1)

L’émission d’un trait d’une durée de 10 secondes après tout envoi de signaux horaires.

(2)

La mission confiée au Bureau international de l’Heure (B.I.H.) de centraliser, discuter et publier les résultats de l’opération.

(3)

L’approbation du programme des opérations, exposé dans le Rapport présenté à Cambridge par le Président et le Secrétaire de la Commission.

Le Président est heureux de constater que les propositions de ce Rapport ont pu être réalisées dans une très large part. Il remercie tous les Observatoires et organismes participants de leur collaboration et les félicite vivement de l’activité qu’ils ont déployée pendant la campagne scientifique de 1933.
23. Commission de la Carte du Ciel
Authors: Esclangon M. E. , Bafflaud MM. J. , Baldwin  , Bemporad  , Bhaskaran  , Curlewis  , Delvosal  , Donner  , Dyson  , Favaro  , Furuhjelm  , Gallo  , Herrero  , Jones  , Lagarde  , Lagnila  , Nangle  , Paloque  , Penine  , Picart L. , Plaskett H. H. , Sampson  , Stein  , Stroobant
Published: July 2016

Depuis la réunion de Cambridge, en 1932, la Commission de la Carte du Ciel a vu, avec un profond regret, disparaître son vénérable et eminent Président d’Honneur, M. Benjamin Bafflaud, artisan de la première heure de l’œuvre de la Carte du Ciel. Il était l’un des rares survivants du Congrès initial de Paris en 1887. Comme directeur de l’Observatoire de Toulouse d’abord, de l’Observatoire de Paris ensuite, il avait pris aux travaux une grande part personnelle; comme Président du Comité international permanent, il avait été, pendant de longues années, l’ordonnateur et l’animateur de l’œuvre. Il n’avait jamais cessé de s’en occuper.
27. Commission des Étoiles Variables
Authors: Nijland M. A. A. , Dugan M. R. S. , Banachiewicz MM. , Bemporad A. , Blažko  , Campbell L. , Cox  , Danjon  , de Roy  , Dufay  , Einbu  , Gadomski  , Gerasimovič  , Graff  , Grouiller  , Guthnick  , Hellerich  , Henroteau  , Hertzsprung  , Hoffmeister  , Jacchia  , Jordan  , Kordy-lewski  , Kukarkin  , Lacchini  , Ludendorff  , Luplau-Janssen  , McLaughlin  , Merrill  , Mitchell  , Nielsen  , Pickering D. B. , Prager  , Sawyer Mlle , Shapley MM. , Silva  , Steavenson  , Stebbins  , Strömgren E. , Swope Mlle , Bruggencate MM.ten , Voûte  , Zessewitch
Published: July 2016

It is well-nigh impossible to give, in a short report, an adequate idea of the enormous activity in Variable-Star Astronomy during the past three years. Without attempting to be complete I shall give a summary of the most important recent occurrences in this field of research.

Statistical data for eclipsing binaries were given by Gaposchkin (Veröff. Berlin-Bab. 9, Heft 5), for long-period variable stars by Ludendorff (Sitz.-ber. Ak. d. Wiss. Berlin, 1932), Thomas (Veröff. Berlin-Bab. 9, Heft 4) and Sterne and L. Campbell (Harvard Annals).

Some valuable catalogues have been issued: a Finding List for Observers of Eclipsing Variables by Dugan (Princeton Contr. No. 15), a Catalogue of Eclipsing Variables, together with a Program of Investigations, by Martinoff (Engelhardt Obs. Bull. No. 2), a Catalogue and Ephemeris of Short-period Cepheids by Zessewitsch (Len. Un. A. 0. Bull. No. 3).
33. Commission de la Statistique Stellaire
Authors: Lindblad M. , Bok MM. , Eddington  , Hertzsprung  , Hirayama S. , Lundmark  , Luyten  , Malmquist  , Mineur  , Oort  , Pannekoek  , Russell  , Schatén  , Schilt  , Seares  , Strömberg  , van Maanen  , van Rhijn  , von der Pahlen
Published: July 2016

In the wide field of research covered by the Commission considerable progress has been made in recent years, and it is only possible here to touch briefly on the results of a few lines of investigation, without any attempt to completeness.

Stellar luminosities. On the basis of the new list of Mount Wilson spectroscopic parallaxes and a compilation of the long series of modern trigonometric parallaxes A. van Maanen finds 617 objects within a distance of 20 parsecs from the sun. It is very doubtful, however, if we know all the stars even in the region of 5 parsecs radius. Almost all the known stars within 20 parsecs belong to the main sequence, the faintest star being of absolute magnitude +16.6. The most interesting deviations from the main sequence are the three “white dwarfs”, Сотр. of Sirius, Comp. o2 Eridani, and van Maanen’s F type star. G. P. Kuiper lists 3 additional white dwarfs at larger distances which were estimated to be of types Bo, B7 and A2. For the first two stars, A.C. 70°8247 and Wolf 1346, a revision of the spectral types by Adams and Humason gives A2 and A5, respectively, although the spectra differ considerably from normal ones. The A2 star in Kuiper’s list is the one discovered by Oosterhoff in the region of the cluster h, X Persei; its spectral characteristics have been examined by Öhman and by Humason. The absence of the high-numbered members of the Bahner series and of the continuous absorption at the Balmer limit seems to be an important criterion of such stars. A white dwarf of quite peculiar spectrum (type probably about B8) is the companion of o Ceti discovered spectro-graphically by Joy in 1922. There appear several additional deviations towards faint magnitudes from the main sequence which may be classed more or less safely among the white dwarfs. A few such cases have been discussed at Lund by J. Tuominen.
Commission 13. (Solar Eclipses.)
Authors: Stratton F. J. M. , Minnaert M.
Published: July 2016

At the request of the President, Prof. Sotome gave some information about the possibilities of observing in Japan and offered to give any additional details to all those who were interested. In the best central part there was about 40% probability of a clear sky.

No Russian astronomer being present, Prof. Carroll reported that scientific workers in Russia were anxious to give all possible cooperation; he intended to go himself to Russia this summer, in order to prepare an expedition to Siberia, and he was prepared to get all questions answered which any one should wish to put. Letters about this subject must reach him before the end of August.
Commission 29. (Stellar Spectra.)
Authors: Russell H. N. , Swings P.
Published: July 2016

1. Le rapport distribué aux personnes présentes commence par un court aperçu des principaux travaux faits dans le domaine des spectres stellaires depuis l’assemblée précédente. Le Président demande si l’une ou l’autre personne désire suggérer des modifications ou compléments à cet exposé. Aucune observation n’est présentée.

2. Le rapport du sous-comité chargé de l’examen des critères de classification des spectres stellaires est ensuite mis en discussion. Une lettre de Mme Payne-Gaposchkin a été reçue à ce sujet; Mme Payne-Gaposchkin signale que des détails manquent dans le rapport du sous-comité; elle demande aussi que soient définis clairement les types A7 et K7 actuellement utilisés fréquemment, ainsi que les symboles g et d distinguant les étoiles géantes et naines.
3. Commission des Notations, des Unités et de L’économie Des Publications
Authors: Strömgren M. E. , Bosler MM. , Chant  , Eddington  , Grabowski L. , Horn d’Arturo  , Lou Kao , Ludendorff  , Russell  , Schlesinger
Published: July 2016

At the Paris meeting in 1935 the following resolutions of Commission 3 were adopted by the Union:

1.

Que la liste préliminaire de notations préparée par le Président de la Commission soit, après certaines modifications, imprimée dans les Transactions de l’Union à titre de liste recommandée provisoirement, et que les astronomes intéressés à la question soient invités a adresser au Président de la Commission les changements qu’ils y suggéreraient.

2.

Que l’Union donne son approbation à la publication d’un complément mentionnant les changements et additions à la liste des Observatoires et des Astronomes publiée en 1931, sous les auspices de l’Union, par l’Observatoire Royal d’Uccle.

3.

Que l’Union consacre, si possible, une somme n’excédant pas cinq cents francs or, à aider la publication de ce complément.

The provisional list of notations was printed, as an appendix to the report of Commission 3, Trans. I.A.U. 5, 18, 1935. A number of astronomers communicated to the President of the Commission suggestions of changes. On the basis of these suggestions a corrected list of notations was prepared.

Reprints of this list were circulated to the various observatories and suggestions of changes invited. In response to this a number of suggestions were received.
5. Commission des Analyses de Travaux et de Bibliographie
Authors: Lundmark M. K. , Collinder M. , Bourgeois MM. P. , Brasch  , Chatelu J. , Pluvinel de la Baume , de Vos van Steenwijk  , Dittrich  , Emanuelli  , Gabba  , Gastardi E. , Grouiller  , Neubauer  , Neugebauer  , Nordenmark  , Pogo  , Selga  , Shinjo  , Yashnov
Published: July 2016

At the Paris congress in 1935, Messrs Dittrich, Brasch and Pogo had proposed that Commission 5 should undertake the publication of classical works of astronomy (such as Ptolemy’s Almagest, the works of Copernicus, etc.) which were untranslated or for other reasons difficult of access. The commission decided to form a sub-commission, consisting of Mr Stroobant and the gentlemen named above, to study this question, especially the means for its realization. Mr Stroobant had announced his desire to take this work in hand personally. Prof. Stroobant, however, having deceased in July 1936, and his health having been deficient during several months in advance, the sub-commission has not been able to continue its work. This is a question that ought to be taken up at the Stockholm meeting.
II. Commission des Phénomènes Chromosphériques
Authors: D’Azambuja M. L. , Abetti MM. , Bosler  , Brunner  , Butler  , da Costa Lobo F. M. , Deslandres  , Donitch N. , Evershed  , McMath  , Merlin  , Newbegin  , Newton  , Nicholson  , Pettit  , Rodés  , Rowland  , Royds  , Sotome  , Unsöld  , Woltjer
Published: July 2016

La Commission vient de subir une lourde perte en la personne de George Ellery Hale, Directeur honoraire de l’Observatoire du Mont Wilson, décédé le 21 février 1938, à l’âge de 70 ans.

L’enregistrement des phénomènes chromosphériques qui sert de base aux relevés et statistiques publiés régulièrement par divers observatoires, a été poursuivi sans changements notables depuis le dernier congrès. Le tableau reproduit dans Trans. I.A.U. 5, 59, 1935 et dans lequel sont groupés les renseignements relatifs à ces travaux d’observation courante, est donc toujours valable.
15. Commission Pour L’étude Physique des Comètes
Authors: Baldet M. F. , Bobrovnikoff MM. , Crommelin  , Kopff  , Orlov  , Quénisset  , van Biesbroeck  , Vorontsov-Velyaminov  , Vsekhsvyatsky  , Wilk
Published: July 2016

Depuis le Congrès de 1935, au cours duquel la Commission 15 fut créée, des travaux de plus en plus nombreux ont été effectués sur les sujets rentrant dans le cadre de cette Commission. Quoique aucune grande comète ne soit apparue pendant les trois années 1935-36-37, deux comètes moyennes visibles à l’œil nu: Peltier (1936a) et Finsler (1937f) ont permis des recherches variées auxquelles il faut ajouter celles qu’on a pu faire sur les comètes plus faibles ou moins bien placées: Johnson (1935a), Whipple (1937b), Wilk (1937c) et Encke (1937h). Des études théoriques et statistiques et des ouvrages d’ensemble ont complété ces travaux.
18. Commission des Longitudes par Télégraphie Sans fil
Authors: Perrier Général G. , Lambert M. A. , Baîllaud MM. R. , Bianchi  , Bowie W. , Coculesco  , Lobo F. M. da Costa , de Lemos  , Esclangon  , Fayet  , Fichot  , Guyot  , Hasimoto  , Ivanov  , Jackson J. , Jeffers  , Jones Spencer , Jouaust  , Kohlschütter E. , Krassowski J. , Lejay  , Moreau  , Niethammer  , Nörlund  , Nušl  , Pavlov  , Plakidis  , Sampson  , Silva  , Sollenberger  , Stewart R. M. , Stoyko  , Tsiang  , Volta  , Watts  , Witkowski  , Zimmer
Published: July 2016

La centralisation au Bureau international de l’Heure des résultats d’observations de l’Opération internationale de 1933 a été très lente, puisque les dernières données attendues ont été reçues vers la fin de 1937.

Le nombre des stations ayant coopéré à l’Opération internationale et ayant transmis leurs observations à l’organisme centralisateur s’élève à soixante et onze. Ainsi qu’il a été expliqué à notre Commission mixte, lors du Congrès de l’Union géodésique et géophysique internationale tenu à Édimbourg en 1936, ces stations ont été réparties en trois groupes:

Le Ier comprenant vingt Observatoires, disposant chacun de plusieurs horloges de première classe (soit à poids sous pression et à température constantes, soit à quartz piézoélectrique);
26. Commission des Étoiles Doubles
Authors: Hertzsprung M. E. , Aitken MM. , Baize  , Dawson B. H. , Finsen  , Giacobini  , Kuiper  , Luyten  , Maggini  , Olivier  , Przybyllok  , Rabe  , Rossiter  , Russell  , van Biesbroeck  , van den Bos  , Voûte  , Zagar
Published: July 2016

The discovery of southern double stars carried out at Bloemfontein by Dr R. A. Rossiter and his collaborators with the 27-inch Lamont refractor has recently been brought to a close. The total number of new pairs found in this way and published now amounts to 5252. It is a great satisfaction to know that Dr Rossiter has been enabled to complete his work by micrometrical measures of these objects. Only in this way can full value be given to our knowledge of these new pairs.
31. Commission de L’heure
Authors: NöRlund M. N. E. , Perrier G. , Esclangon M. E. , Baillaud MM. R. , Banachiewicz  , Bianch  , Carnera  , Dneprovsky  , Dyson  , Fayet  , Gallo  , Guyot  , Lambert A. , Lejay  , Moreau  , Niethammer  , Picart L. , Postoev  , Preipich-Freyberg  , Sampson  , Silva  , Sollenberger  , Sotome  , Stewart  , Stoyko  , Tinoco  , Verbaandert  , Voûte
Published: July 2016

Durant la période de 1933 à 1936 le Bulletin Horaire a donné les heures définitives des signaux horaires d’après la moyenne de 15 observatoires. A partir du Ier janvier 1937 on introduit trois observatoires en plus (Kharkov, Manille et Tokyo), qui communiquent régulièrement leurs résultats au B.I.H.

Au Bureau International de l’Heure certains perfectionnements sont actuelle ment en voie de réalisation. Il s’agit d’une horloge à diapason d’une part, et, de l’autre, d’un ensemble nouveau pour l’émission des signaux horaires. M. Lambert va donner une communication sur ce sujet.
32. Commission des “Selected Areas”
Authors: Van Rhijn M. P. J. , Adams MM. W. S. , Alden  , Becker F. , Gaposchkin Mme Payne , Hins MM. , Knox-Shaw  , Kohlschütter A. , Schlesinger  , Schwassmann  , Seares  , van Maanen
Published: July 2016

The following lines give a summary of the work concerning Kapteyn’s Plan of Selected Areas up to December 1937.
36. Commission de la Spectrophotométrie
Authors: Pannekoek M. A. , Baillaud MM. J. , Barbier  , Beals  , Carroll  , Chalonge  , Davidson C. R. , Dufay  , Dunham  , Eddington  , Elvey  , Fabry Ch. , Greaves  , Hogg F. , Kienle  , Lindblad  , Menzel  , Milne  , Minnaert  , Mulders  , öhman  , Plaskett H. H. , Redman  , Righini  , Rosseland  , Russell  , Sampson  , Struve  , Tiercy  , Unsöld  , Whipple  , Williams E. G. , Woolley  , Yü
Published: July 2016

At the first meeting of the newly formed Commission on Spectrophotometry, at Paris in 1935, a thorough discussion, aided by several reports, took place on the principles of this branch of astrophysics. So it will be sufficient now to treat only such special points of theory and practice as have won interest by researches of the last few years.
5. Study of Cosmic Rays by Rockets and Sputniks in the U.S.S.R.
Authors: Vernov S. N. , Chudakov A. E.
Published: July 2016

In the U.S.S.R. the study of cosmic rays by rockets was started in 1947.

In the beginning, with the help of Geiger counters the number of charged particles was measured, and the formation of the electron-photon component in the interaction of primary particles of cosmic rays with nuclei of light elements was investigated.
4. Ephemerides
Authors: Wilkins G. A. , Kovalevsky J. , Clemence G. M. , Chebotarev G. A. , Duncombe R. L. , Fricke W.
Published: July 2016

The appended reports of the directors of the national ephemeris offices provide a record of the current activity in the publication and preparation of astronomical ephemerides, including those published for use by navigators and surveyors and those prepared for astronomers whose special needs are not met in the printed almanacs. A brief review of the relevant work of other institutions and individuals is also given in the appendix. The reports also cover to some extent activities in positional astronomy and celestial mechanics (i.e. in the fields of interest of Commissions 7, 8, 17, 19, 20 and 31). This report is therefore restricted to reviewing, firstly, the action that has been taken on matters raised at and since the 1967 meetings of the Commission and, secondly, the matters that will require attention at and after the 1970 meetings.

Before that review, it is appropriate to pay tribute to the memory of that almost legendary astronomer, Gaston Fayet, who died on 27 December 1967 at the advanced age of 93. As member of the Bureau des Longitudes responsible for the production of the Connaissance des Temps from 1930 to 1961, and President of Commission 4 from 1938 to 1952, he contributed greatly to our subject, in addition to his researches in other fields particularly in respect of the minor planets.
Appendix: Reports of the Directors of the National Ephemerides
Authors: Abalakin V. K. , Kovalevsky J. , Sadler D. H. , Fricke W. , Sinzi A. M. , Lahiri A. M. , Rodriguez M. , Duncombe R. L. , Wilkins G. A.
Published: July 2016

During the period under review two issues of the Astronomical Yearbook of the U.S.S.R. for the years 1971, 1972 have been published, and that for 1973 is in preparation. The positions and proper motions of the stars are in the FK4 system as recommended by Commission 4 in 1961. Further, as recommended at the meeting in Hamburg in 1964 (Trans. IAU, 12 B (1964), 105,1966) the IAU System of Astronomical Constants has been introduced into the tabulations of the day numbers, solar and lunar eclipses, ephemerides for physical observations of planets, and the factors S &C. The corresponding differential corrections to the Moon’s ephemeris as well as re-calculated eclipse data for 1971 have been tabulated separately in the Appendix to the Yearbook for 1971. As from the edition of the Yearbook for 1972, the lunar ephemeris j = 2 will be published in accordance with the recommendations adopted in Prague in 1967.

The regular publication of the ephemeris of the lunar crater Mösting A has been continued in the editions of the Yearbook mentioned above.

Fundamental ephemerides of the Sun, Moon, and planets have been printed in full conformity with the first part of the Astronomical Ephemeris circulated in advance by H. M. Nautical Almanac Office, Royal Greenwich Observatory.
Committee 2: Transition Probabilities
Authors: Garstang R. H.
Published: July 2016

A very great deal of work has been done during the last three years on the determination of atomic transition probabilities, and complete coverage here is impossible. Wiese and his staff at the National Bureau of Standards, Washington, have continued to collect all numerical results, and they can supply information as to what is available for any particular atom. They have published (1) a critical compilation of atomic transition probabilities for the atoms sodium to calcium (inclusive) in essentially the same way as an earlier compilation covered hydrogen to neon. At the time of writing a complete new bibliography is also in preparation (2), which will be published as NBS Special Publication 320 and which is complete up to June 1969. Review articles published include that of Layzer and Garstang (3) on theoretical allowed and forbidden transition probabilities, and the two volume conference report (4) covers beam foil spectroscopy (including lifetime measurements) in some detail. A fairly complete review of forbidden line transition probabilities was given by Garstang (5), where references to many original papers may be found. In the following we shall confine ourselves to mentioning a few areas of particular interest; detailed references can be traced through the bibliographies, reviews and abstracting journals.
Report of the Committee on the Spectra of Variable Stars
Authors: Feast M. W.
Published: July 2016

The field covered by this report overlaps particularly with the work of Commissions 29 and 45 whose reports should be consulted. I have been greatly helped by reports on Soviet work by Professor Kukarkin and Dr Boyarchuk and a bibliography of European literature by Bloch.

The Sonneberg programme for determining spectral types of variables has been described by Götz and Wenzel (AN, 290, 99) and several lists have been published in MVS. Bakos is studying high dispersion spectra of a number of variables that are members of visual binary systems.

Stephenson and Terrill (ApJ, 147, 148) and Houk (IB, 228) have given spectral types for a considerable number of long period variables. Terrill (AJ, 74, 413) has made an extensive study of the variation of spectrum with phase for 51 red variables. Deutsch, Keenan and Garrison have continued their extensive programme of spectral classification of Mira variables. Keenan and Dessy (ApJ, 146, 583) suggest that the relatively early spectral type of the very long period Miras (R Cen, R Nor etc.) showing double maxima indicates that the fundamental parameter is the half-period (between successive maxima). A similar conclusion (ApJ, 93, 380; MN, 125, 367) was reached earlier by others on the basis of the correlation with period of the difference between absorption and emission velocities. Feast has used K subgiant companion of U Men to derive an absolute magnitude of — 0m.5 for the Mira star. The radial velocity of the companion agrees with the absorption velocity of the variable near maximum (Obs.).
Report of the Working Group on Flare Stars
Authors: Andrews A. D. , Čugainov P. F. , Geršberg R. E. , Oskanian V.
Published: July 2016

The Working Group was organized in order to promote and develop the cooperative studies of flare stars. Up to the present time our observation programmes were restricted to the UV Ceti-type stars only. Organizational activities followed the aims:

(1) To extend the existing network of photoelectric observers in order to provide 24-hour coverage of a star during selected sessions lasting usually 14 days.

(2) To collect data using standardized techniques in order to study frequency of stellar flares and secondary variations.

(3) To provide optical coverage for simultaneous radio, spectroscopic and polarimetric observations.
Working Group on Galaxy Photometry
Authors: de Vaucouleurs G.
Published: July 2016

1. A tabular presentation has been adopted and the report does not cover work in the U.S.S.R. During the report period Circular No. 6 (Report on Prague Meeting) and a Technical Supplement, No. 6a, were distributed. Work on standard luminosity profiles for a few well-observed galaxies (NGC3115, 3379, 4486) progressed more slowly than expected, but provisional results will be available for presentation at the 1970 meeting.

2. On the observational side the major event to report is the publication of an Atlas de Galaxias Australes by J. L. Sěrsic; it gives photographs, descriptions and detailed surface photometry of 50 southern galaxies observed with the 150-cm reflector of Cordoba Observatory. Another important contribution is the dissertation of H. D. Abies on “Optical Study of Nearby Galaxies” of interest to radio astronomy. The isophotometric atlas of 70-80 galaxies and UBV catalogue of 500 galaxies observed by G. and A. de Vaucouleurs at Mt. Stromlo and McDonald Observatories and by H. D. Abies at Flagstaff, F. Bertola at Asiago and other collaborators is being prepared for publication in 1970-71.

On the technical side the rapid development of automatic digital methods for data recording and processing should lead to a great acceleration in the production of precise isophote maps, but most commercial instruments are still deficient with respect to mechanical precision, optical design (stray light, beam definition) and electrical stability.
29. Stellar Spectra
Authors: Feast M. W. , Fujita Y. , Bappu M. K. V. , Herbig G. , Houziaux L. , Kopylov I. M. , Przybylski A. , Sahade J.
Published: July 2016

Material for this report was collected by the President, Vice-President and Members of the Organizing Committee. The President is, however, responsible for the form in which the report now appears. A number of special abbreviations in the references are explained in the report of Committee 27a. In addition, 3rd Harvard = 3rd Harvard-Smithsonian Conference on Stellar Atmospheres (1968). The field of Commission 29 overlaps particularly with those of 9, 27a, 36, 44 and 45 whose reports should be consulted. Since the last IAU meeting 29 has co-sponsored the following meetings: IAU Colloquium No. 4 on Stellar Rotation (Columbus, Ohio, September 1969); IAU Symposium No. 36, Ultraviolet Stellar Spectra and Related Ground-Based Observations (Lunteren, June, 1969); Second Trieste Colloquium, Mass Loss from Stars (September, 1968). We are also co-sponsoring IAU Symposium No. 42 on White Dwarfs to be held in Scotland (August, 1970). The thanks of the commission are due to their representatives on the organizing committees of these meetings. Reports from some working groups are appended. The working group with Commission 44 has not felt it necessary to submit a report (its main activity was the organization of Symposium No. 36). Miss Underhill (Chairman) recommends that the working group on Tracings of High Dispersion Stellar Spectra be dissolved.
36. Theory of Stellar Atmospheres
Authors: Underhill A. B. , Cayrel R. , Böhm K. H. , Ivanov V. V. , Jefferies J. T. , Thomas R. N. , Ueno S.
Published: July 2016

This report has been prepared by the President with the assistance of the Vice-President, the Members of the Organizing Committee, V. V. Ivanov, P. Conti and of D. G. Hummer. The work of Commission 36 comes in contact with that of many commissions. Some subjects may be dealt with more fully in those reports; some subjects may have been “unlawfully” included here. Considerable choice has been exercised by the President about what to mention and in which section of the report to place it. The final product is only indicative of the large amount of work going on. An extensive bibliography has been compiled and will be distributed to commission members.

Commissions 12, 27, 29, 44 and 45 deal with observational material which our theories attempt to interpret, thus it is essential to study the reports of these commissions to appreciate the diversity of material for which theories are needed and against which theories may be checked. The theoretical treatment of the problems of planetary atmospheres, Commission 16, is not entirely divorced from that of stellar atmospheres. To set realistic inner boundary conditions on our atmosphere models and on our thinking, we must consider the material of Commission 35 while to set the outer boundary conditions we may consider the physical state of planetary nebulae which is one subject of Commission 34. When we wish to apply ideas about the interactions between radiation, atoms, ions and molecules we use material which lies in the province of Commission 14.
41. History of Astronomy
Authors: Rybka E. , Gingerich O. J. , Fleckenstein J. O. , Hellman C. D. , Horský Z. , Kulikovsky P. G. , Petri W. , Tchenakal V. L.
Published: July 2016

The investigations on the history of astronomy proceed rapidly and concern all branches, viz. the history of astronomy in particular countries, the historical development of the astronomical problems, biographies of astronomers, history of observatories and of astronomical instruments etc. They are being made by professional astronomers and historians of science at observatories and institutions destined for the history of science. The president of Commission 41 cannot give a comprehensive review of all directions of investigations on the history of astronomy, because their results frequently have been published in publications not accessible to the author of this report. The present draft report is based mainly on information received by the president from members and consulting members. Besides, the present report contains short information on the results of international conferences, which were held independently of IAU.
Commission 41: History of Astronomy/Histoire de l’Astronomie
Authors: Razaullah Ansari S. M.
Published: July 2016

The membership of the Commission stands, with the election of 18 IAU members and 12 historians at the XXII GA (1994), at 155 presently (Sept. 1996). Note the increase in membership, which is 24% and which hopefully may go to 30-35% by XXIII GA (1997). The Commission has put a message on WWW for all IAU members/presidents of various commissions to join the Commission 41 in a big way, so that it can extend its scope of activities further. Besides holding a Joint Discussion of its own (No. 17), Commission 41 is co-supporting JDs 8, 20 and 23.
2. Solar granulation photographs from
the stratosphere
Authors: Schwarzschild Martin
Published: July 2016

The Princeton University Observatory carried out last summer three unmanned stratospheric balloon nights for the same purpose as that described in the preceding communication, namely to obtain high-definition photographs of the solar granulation. The special telescope for this purpose was built by the Perkin-Elmer Corporation, the electronic pointing mechanism was constructed by the Boulder Research Laboratories, and the balloons were manufactured and flown by General Mills Inc. The project was sponsored by the U.S. Office of Naval Research and by the U.S. Air Force.
3. Astrophysical measurements from rockets
Authors: Friedman Herbert
Published: July 2016

The X-ray spectrum of a quiet Sun can be approximated by a 500,000° K Planckian distribution. In the absence of coronal excitation, as evidenced by the intensity of the Fe xiv green line, the X-ray spectrum has a short wave-length limit near 20 A. Coronal activity is accompanied by weak emissions down to wave-lengths as short as 6 A, which appear to be associated with coronal hot spots at temperatures of 2 x 106° K or higher.
Models for Source Structure Corrections
Authors: Charlot P.
Published: July 2016

At the milliarcsecond scale, most of the extragalactic radio sources exhibit spatially-extended intrinsic structures which are variable in both time and frequency. Such radio structures set limits on the accuracy of source positions determined with the Very Long Baseline Interferometry (VLBI) technique unless their effects in the astrometric data can be accounted for. We review the modeling scheme for calculating source structure corrections and discuss the magnitude and impact of these effects for the sources that are part of the International Celestial Reference Frame (ICRF). Results obtained by applying source structure corrections to actual VLBI observations on the time-varying source 4C39.25 (0923 + 392) are also presented.
Rigid-Earth Nutation Models
Authors: Souchay J.
Published: July 2016

Despite the fact that the main causes of the differences between the observed Earth nutation and that derived from analytical calculations come from geophysical effects associated with nonrigidity (core flattening, core-mantle interactions, oceans, etc…), efforts have been made recently to compute the nutation of the Earth when it is considered to be a rigid body, giving birth to several “rigid Earth nutation models.” The reason for these efforts is that any coefficient of nutation for a realistic Earth (including effects due to nonrigidity) is calculated starting from a coefficient for a rigid-Earth model, using a frequency-dependent transfer function. Therefore it is important to achieve high quality in the determination of rigid-Earth nutation coefficients, in order to isolate the nonrigid effects still not well-modeled.

After reviewing various rigid-Earth nutation models which have been established recently and their relative improvement with respect to older ones, we discuss their specifics and their degree of agreement.
SOFA Software Progress Report
Authors: Wallace P.
Published: July 2016

The IAU set up the SOFA initiative at the 1994 General Assembly, to promulgate an authoritative set of fundamental-astronomy constants and algorithms. At the subsequent General Assembly, in 1997, the appointment of a Reviewing Board and the selection of a site for the SOFA Center (the outlet for SOFA products) were announced. The time since then has been spent developing the specifications for a basic collection of fundamental-astronomy algorithms. Progress has been slow, for a number of reasons: the task is difficult and requires great circumspection; a substantial toolkit of support routines must be adopted or developed before work on the astronomy routines themselves can begin; and it takes time for a geographically dispersed committee to reach a consensus on matters that involve value judgements, such as programming style. However, despite these formidable difficulties, significant progress has been made. A library of 52 vector/matrix routines has been developed, supporting a set of 25 astronomy algorithms. The Reviewing Board is about to start validating these algorithms, at which point they can be released through the SOFA Center.
The Definition of UTC
Authors: McCarthy Dennis D.
Published: July 2016

The current definition of Coordinated Universal Time (UTC) is related to the unpredictable, variable rotation rate of the Earth. This is accomplished by irregular insertions of leap seconds, creating unpredictable discontinuities in UTC. With the increasing importance of a continuous, uniform time scale for users, it is appropriate to re-examine the current definition of this time scale. There are several possibilities to address this problem, and it is appropriate that the International Astronomical Union establish a working group to investigate the continuing need for leap seconds and possible changes in the definition of UTC.
The Effect of Companions on the SIM Reference Frame
Authors: Jacobs Christopher S. , Turyshev Slava G.
Published: July 2016

The Space Interferometry Mission (SIM) is a 10-m Michelson space-based optical interferometer designed for precision astrometry (4μas, 3μas/yr) with better accuracy hoped for over a narrow field of view. It is intended to search for planets and investigate a number of problems in Galactic and extra-galactic astronomy.

The accuracy and stability of SIM’s celestial reference frame is subject to degradation over the 5-year mission from the reflex motion induced by massive companions of the objects used to construct the celestial reference frame. We present the results of simulations which show the sensitivity of reference frame accuracy to companions as a function of mass and period. We assume that pre-launch ground surveys will eliminate all objects with RMS radial velocity > 10 m/s. We further assume that the standard astrometric parameters of position, parallax, and proper motion plus acceleration terms in right ascension and declination will be allowed to absorb reflex motion.
The Parkes Multibeam Pulsar Survey and Interstellar Scattering
Authors: Manchester R.N.
Published: July 2016

The Parkes multibeam pulsar survey is a major survey for pulsars lying within a 10°-wide strip along the southern Galactic plane, using the multibeam receiver on the Parkes 64-m radiotelescope. It is an international collaboration between groups at Jodrell Bank Observatory, Massachusetts Institute of Technology, Bologna Astronomical Observatory and the ATNF. The survey commenced in 1997 August, and has so far succeeded in finding more than 550 previously unknown pulsars. Many of these are distant, with some beyond the centre of the Galaxy according to current models of the interstellar electron density distribution. Interstellar scattering affects the pulse profile of many of the more distant pulsars even at 1374 MHz, the centre frequency of the survey. Preliminary results from the survey are presented.