Messenger No. 29 (September 1982)

« Back to The Messenger home

1-4 (PDF)
J. W. Pel
The Metal Content of Magellanic Cloud Cepheids

ADS BibCode:
1982Msngr..29....1P
Author(s)/Affiliation(s):
Pel, J. W.
AA(Kapteyn Astronomical Institute, Groningen, the Netherlands)
Abstract:
Ever since 1912, when Miss Leavitt discovered the famous period-Iuminosity law for Cepheids in the Magellanic Clouds, the Clouds have played a central role in the study of these important and fascinating pulsating stars. The reason for this is simple: the Magellanic Clouds are relatively small in comparison to their distances from uso When looking at one of the Clouds, we observe therefore stars which are all at approximately the same distance. A second advantage is that the extinction by interstellar dust in the Clouds is much less of a problem than in our own Galaxy, where it is a major obstacle for determinations of absolute magnitudes, distances, and intrinsic colours. Fortunately Cepheids occur frequently, both in the Large Cloud (LMC) and in the Small Cloud (SMC), and since they are supergiants they are still reasonably bright, even at a distance of 50 or 60 kiloparsecs. For an analysis of the relative differences between Cepheids of various periods the Clouds are therefore uniquely suited.
1-1 (PDF)
G. Lyngå
The Users Committee - where the grassroots talk.

ADS BibCode:
1982Msngr..29....1L
Author(s)/Affiliation(s):
Lyngå, G.
AA(Lund Observatory, Chairman of the UC)
Abstract:
Once a year, a sunny day in May, the Users Committee meets. Each national representative has fram his colleagues at home brought a long list of complaints, suggestions and expressions of gratitude to ESO.
1-1 (PDF)
ESO
M. K. V. Bappu, 1927 - 1982

ADS BibCode:
1982Msngr..29....1.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
It is in the deepest sorrow that we have to announce the untimely death 01 Prof. M. K. V. Bappu, Directorolthe Indian Institute 01 Astrophysics, Bangalore, and President 01 the International Astronomical Union. He passed away in Munieh, on Augusl19, 1982, during a visil to ESO, following complications after major heart surgery. An obituary will lollow in lhe nexl issue 01 the Messenger.
4-4 (PDF)
ESO
List of Preprints Published at ESO Scientific Group

ADS BibCode:
1982Msngr..29....4.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
201. H. PEDERSEN, J. VAN PARADIJS, C. MOTCH, L.COMINSKY, A. LAWRENCE, W. H. G. LEWIN, M. ODA, T. OHASHI and M. MATSUOKA: Optical Bursts from 4U/MXB 1636-53. Astrophysical Journal. June 1982.
5-8 (PDF)
E.H. Geyer, A. Hanel
A sit Vidicon for Surface Photometry

ADS BibCode:
1982Msngr..29....5G
Author(s)/Affiliation(s):
Geyer, E.H.; Hanel, A.
AA(Observatorium Hoher List, Daun) AB(Observatorium Hoher List, Daun)
Abstract:
The study of surface brightness distributions of extended cosmic light sources is an essential observational approach to understand their spatial structure. In general, however, surface photometry is difficult to interpret without other supporting observations like spectroscopy, which yields the velocity field or other physical parameters. The reason is that the surface illumination is the total number of light sources within a conical column along the line of sight. This cone is the solid angle of an individual picture element ("pixel") projected onto the sky by the telescope optics. Therefore, astronomical surface photometry yields the surface density of cosmicallight sources, which is badly contaminated by light sources in the foreor background or even in the surrounding field.
5-5 (PDF)
ESO
Announcement - ESO Workshop on Primordial Helium

ADS BibCode:
1982Msngr..29....5.
Author(s)/Affiliation(s):
ESO
AA(ESO)
8-11 (PDF)
B. Pettersson
Dust and Young Stars in Puppis

ADS BibCode:
1982Msngr..29....8P
Author(s)/Affiliation(s):
Pettersson, B.
AA(Astronomiska Observatoriet, Uppsala)
Abstract:
Two decades aga the presence of a group of young stars in the constellation Puppis was noted and described by Westerlund (Mon. Not. R. Astr. Soc. 127,71,1963). This group appears to form an association of hot and luminous o and B stars also containing the long-period cepheid RS Puppis. The association was named Puppis OB 3. In the region occupied by the association a number of small and peculiar bright nebulae were noted as weil as several dark globules and dust lanes (Fig. 1). Also present in the region is the H 11 region RCW 19 which obviously is excited by the most luminous of the association members. The age of the association was estimated from the most luminous member, the 07f star HO 69464, to be no more than 4 . 106 years. Thus the stage seemed to be set for the scrutinizing of a relatively restricted region of recent star formation concerning the content of both stellar and interstellar material. The following is only intended to be a progress report of this project as some of the recent observational material is still being analysed.
8-8 (PDF)
ESO
Announcement - ESO Conference on Very Large Telescopes - Their Instrumentation and Programmes

ADS BibCode:
1982Msngr..29R...8.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
Announcement - ESO Conference on Very Large Telescopes - Their Instrumentation and Programmes
8-8 (PDF)
ESO
The Proceedings of the ESO Workshop on the Need for Coordinated Ground-Based Observations of Halley's Comet now Available

ADS BibCode:
1982Msngr..29Q...8.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
The Proceedings of the ESO Workshop on the Need for Coordinated Ground-Based Observations of Halley's Comet now Available
11-11 (PDF)
ESO
Applications for Observing Time at La Silla

ADS BibCode:
1982Msngr..29...11.
Author(s)/Affiliation(s):
ESO
AA(ESO)
12-13 (PDF)
C. Bertout
The UPS and Downs of Coordinated Observations

ADS BibCode:
1982Msngr..29...12B
Author(s)/Affiliation(s):
Bertout, C.
AA(Landessternwarte Heidelberg-Königstuhl)
Abstract:
T Tauri stars are certainly not the only celestial objects for which coordinated observations are of interest. But their behaviour is sometimes so erratic that it is crucial to learn more about the range of the variations and about the correlations between variations in different wavelength domains than is allowed by one-telescope observations. Coordinated observations can overcome this limitation, but bring in their own problems. The question of the mass-flux in the envelopes of T Tauri stars can serve as a first example of how coordinated observations can help. By the end of the nineteen-fifties, it was accepted that T Tauri stars were newly-formed stars, still associated with the clouds from which they were born, and that they were losing mass. Observational evidence of mass-Ioss was confirmed when L. V. Kuhi derived, by modeling line profiles, mass-Ioss rates up to 6 . 10-7 M0 yr-1 . The belief that T Tauri stars had strong stellar winds went unchallenged until the late sixties, when M. F. Walker reported that a subclass of T Tauri stars, which he named YY Orionis stars, showed spectroscopic evidence for mass accretion. Our group at the Heidelberg Observatory studied active T Tauri stars extensively, and was able to show that a number of them were, at times, apparently accreting material. Even more confusing, Krautter and Bastian (1980, Astronomy and Astrophysics 88, L6) reported changes in the direction of the mass-f1ow on timeseales of days in DR Tauri, and even found evidence for simultaneous infall and outflow.
13-15 (PDF)
ESO
Visiting Astronomers (October 1, 1982-April 1, 1983)

ADS BibCode:
1982Msngr..29...13.
Author(s)/Affiliation(s):
ESO
AA(ESO)
15-17 (PDF)
T. Neckel
Observations of Bipolar and Compact HII Regions

ADS BibCode:
1982Msngr..29...15N
Author(s)/Affiliation(s):
Neckel, T.
AA(Max Planck Institute for Astronomy, Heidelberg)
Abstract:
Several investigations carried out during the last years at the Max Planck Institute for Astronomy in Heidelberg have dealt with the bipolar compact H 11 region S 106. The essential structural features of this object are: (i) There is only a single exciting star in the centre of the nebula, (ii) this star is surrounded by a disk of dust that we are seeing edge on. This disk of dust divides the nebula into two "lobes". It causes a visual extinction of the central star of about 20 magnitudes, for which reason it can be photographed only at infrared wavelengths (Eiroa, C., Elsässer, H., and Lahulla, J. F. 1979, Astronomy and Astrophysics 74, 89), whereas the light of the central star can get through the disk in the perpendicular direction. A digitized near infrared photograph of S 106 taken by Elsässer and Birkle with the 1.23 m telescope of Calar Alto is shown in Fig. 1.
15-15 (PDF)
ESO
Personnel Movements

ADS BibCode:
1982Msngr..29...15.
Author(s)/Affiliation(s):
ESO
AA(ESO)
18-19 (PDF)
A. R. Condal
Sulfur Abundances in Gaseous Nebulae

ADS BibCode:
1982Msngr..29...18C
Author(s)/Affiliation(s):
Condal, A. R.
AA(Atmospheric Environment Service, Toronto)
Abstract:
The determination of abundances in planetary nebulae (PN) and H 11 regions is important for studying the present and past chemical composition of galaxies. Its derivation from the spectral-Iine intensities involves basically the following steps:
References:
Dinnerstein H. L., 1980, Ap. J. 237, 486.
Natta, Ä., Panajia, N., Preite-Martinez, Ä., 1980, Ap. J. 242, 596.
Peimbert, M., Costero, R., 1969, Bol. Obs. Tonantzintla Y Tacubaya,5,3.
19-20 (PDF)
H. J. Schober, J. Surdej
Asteroid Rotation - Hunting for a Record - 1689 Floris-Jan

ADS BibCode:
1982Msngr..29...19S
Author(s)/Affiliation(s):
Schober, H. J.; Surdej, J.
AA(Institute for Astronomy, Graz, Austria) AB(Institut d'Astrophysique, Liege, Belgium)
Abstract:
Last year, in June 1981 - ESO Messenger No. 24, p. 22-23 - H. J. Schober published areport on "Spinning Asteroids and Photometry". There he mainly gave a general introduction about what can be done using UBV photometry in order to derive physical properties of asteroids such as geometrie forms, diameters, reflectance on the surface, bimodality of asteroids with respect to typology. A special effort was made to report about the activities to deal with asteroids as "variable objects" like variable stars - showing Iightcurves with defined rotation rates to be derived. Among asteroids it was stated that the longest rotation periods found before 1975 were not larger than 20 hours - followed by 654 Zelinda 31 ~9 (1975). 393 Lampetia 38h7, 128 Nemesis 39h0 (1979), 709 Fringilla 52h4 (1979) and 182 Eisa 80~00 (1980), the latter corresponding to 3d33.
20-23 (PDF)
J. Brand
The Atmospheric Transmission at La-Silla at 230-GHZ

ADS BibCode:
1982Msngr..29...20B
Author(s)/Affiliation(s):
Brand, J.
AA(Sterrewacht Leiden)
Abstract:
From April to November 1981, ESO La Silla was host to a team of observers from the Netherlands, forming the "CO group". During this time they applied themselves to detecting radiation of the CO moleeule at 230 GHz, using the CAT and their own heterodyne (sub-)millimetre wave receiver. In general the importance of CO observations lies in the fact that CO is, after molecular hydrogen, the most abundant moleeule in interstellar space while its (dipole) rotational transitions can be much more easily detected than the very weak (quadrupole) rotational transitions of H2; the rotational levels of CO are believed to be excited by collisions with other particles, mostly H2, and therefore, by studying the distribution and kinematics of CO one gets indirect information on those properties of H2.
References:
Lidholm, S. and de Graauw, Th: 1979, Fourth International Conference on Infrared and Millimeter Waves and their Applications, Florida 1979, p. App. 38.
23-23 (PDF)
J. F. R. van der Ven
A New System to Eliminate Gear Backlash in Telescopes

ADS BibCode:
1982Msngr..29...23V
Author(s)/Affiliation(s):
van der Ven, J. F. R.
AA(ESO-La Silla)
Abstract:
Preloading a telescope geardrive, to eliminate backlash, always has been a major design aspect in telescope engineering. One of the oldest systems was to preload each axis with a steel cable, wrapped around the axis and loaded with a sufficient heavy weight, to keep the mating flanks of the gearwheel in contact under all circumstances, e.g. during windforces, unbalance, etc.
24-27 (PDF)
R. Wilson
Progress on the 3.5M New Technology Telescope NTT

ADS BibCode:
1982Msngr..29...24W
Author(s)/Affiliation(s):
Wilson, R.
AA(ESO)
Abstract:
Almost two years have gone by since the first article on the ND written by my former colleague Wolfgang Richter appeared in the Messenger (1). In spite of the disruption due to the move from Geneva to Garching and the loss at that time of all the mechanics statt who had worked on ESO telescopes, we can, I think, be satisfied with the progress made. Quite fundamental to this progress is, of course, the funding. This depended on the entry of Switzerland and Italy (announced in the Messenger No. 27 and 28 respectively) into ESO. We in the ND team are particularly happy about these events, for otherwise the ND could not have become a "real" project with a "real" budget. The approved budget is about DM 24 million (1982), including transport and contingency, which is less than one third of the budget of the existing ESO 3.6 m telescope at La Silla (about DM 68 million - 1974).
References:
W. Richter: "New Technology Telescope", The Messenger,No. 27, Sept. 1980, p. 19.
R. N. Wilson: "Image quality and high resolution in future telescopes", Proceedings ot the ESO Conterence on Scientific Importance of High Angular Resolution at IR and Optical Wavelengths", Munich 1981, p. 67.
R. N. Wilson: "Image quality considerations in ESO telescope projects", Optica Acta, 29 (7), July 1982, p. 985.
F. Franza and R. N. Wilson: "Status of the European Southern Observatory New Technology Telescope", SPIE Conference on "Advanced Technology Optical Telescopes", Tueson, March 1982, Paper 332-11 (SPIE Proceedings Volume 332).
J. R. P. Angel: "Very Large Ground-Based Telescopes for Optical and IR Astronomy", Preprints of the Steward Observatory >No. 356, 1982, p. 15.
M. Tarenghi and M. Ziebell: "The European Southern Observatory Automatie Prime Focus Camera and the General Problem of Remote Control", SPIE Conference on "Instrumentation in Astronomy IV", Tueson, March 1982, Paper 331-58 (SPIE Proceedings Volume 331).
B. Platt and R. V. Shack: Optical Sciences Center Newsletter,University 01 Arizona, Tueson, 5 (1), March 1971, p. 15.
F. Franza, M. Le Luyer and R. N. Wilson: "ESO 3.6 m telescope: The adjustment and test on the sky 01 the PF optics with
the Gascoigne plate correctors", ESO Technical Report No. 8, Oct. 1977.
Wm. LasselI: "Description 01 an observatory erected at
Starfield, near Liverpool", Memoirs of the Royal Astronomical Society, XII, 1842, p. 265.
G. Schwesinger: "Support conliguration and elastic
deformation 01 the 1.5 m prime mirror of the ESO Couda Auxiliary Telescope (CAT), ESO Technical Report No. 9, March 1979.
J. R. P. Angel and J. M. Hili: "Manulacture ollarge glass honeycomb mirrors", SPIE Conference on "Advanced Technology Optical Telescopes", Tueson, March 1982, Paper 332-38 (SPIE Proceedings Volume 332).
J. G. Barnes 111, ed.: Proceedings of the 300 inch Optical Conference, March 1982. Dept. of Astronomy, UT Austin, to be published shortly.
27-27 (PDF)
ESO
Comite de los Usuarios

ADS BibCode:
1982Msngr..29Q..27.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
EI Comita de los Usuarios se reune una vez al ano. Cada representante trae de sus colegas nacionales una larga lista de quejas, sugerencias y expresiones de gratilud para ESO.
27-27 (PDF)
ESO
Una visita en Sud America

ADS BibCode:
1982Msngr..29R..27.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
Oisfrute de una estadfa en el Hotel La Silla, el mejor hotel de Sud America con su tan unica atmosfera extraterrestre! Los espera su calificado personal de experimentados hoteleros, jefes de cocina, etc., ansiosos todos de satisfacer sus deseos hasta el mas mfnimo detalle. Naturalmente nuestro espacioso restaurant de tres estrellas ofrece un completo surtido de exquisitas comidas y deliciosos tragos (conocedores usualmente eligen "Oelicia Orion" 0 "Centauro Especial"). EI servicio cempleto durante 24 horas incluye nuestra ya mundialmente famosa "Cena de medianoche para los miradores de estrellas", por eso - no olvide: No pierda la oportunidad de una estadfa en EL HOTEL LA SILLA - una experiencia maravillosa!
27-27 (PDF)
ESO
Paying a Visit to South America?

ADS BibCode:
1982Msngr..29S..27.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
Stay at the LA SILLA HOTEL, the top hotel of South America with this unique extraterrestrial atmosphere! A fully qualified staft of experienced hoteliers, chefs, etc. are awaiting you - eager to care for your needs - down to the smallest details. ... Of course, our spacious three-star restaurant ofters you a whole range of exquisite meals and drinks (connoisseurs usually go for "Orions delight" or "Centaurus Special"). Full service 'round the clock includes our world-famous "Star gazers midnight supper" - so remember: Oon't miss an opportunity to stay at the LA SILLA HOTEL - a heavenly experience!
28-28 (PDF)
ESO
Progreso con el "Telescopio de Nueva Tecnologia" de 3.5 m (NTT)

ADS BibCode:
1982Msngr..29Q..28.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
Desde septiembre de 1980 cuando el primer artlculo sobre el Telescopio ESO de Nueva Tecnologla de 3.5 m fue publicado en "EI Mensajero", el diserio para este instrumento ha hecho progresos satisfactorios.
28-28 (PDF)
ESO
Algunos Resumenes

ADS BibCode:
1982Msngr..29R..28.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
La agenda comienza con un resumen de parte dei Director General: estado de los proyectos de telescopios mas importantes, instrumentaci6n futura y otros asuntos. Luego el Director en Chile y el Jefe de TRS describen las condiciones presentes en que se encuentran los instrumentos, los problemas que han surgido y aquellos que se esperan. Luego estos puntos son disculidos por el Comite.