Messenger No. 30 (December 1982)
1-1 (PDF)
Twenty Years ESO
ADS BibCode:
1982Msngr..30Q...1W
Author(s)/Affiliation(s):
Woltjer, L.
AA(Director General)
Abstract:
On the 5th of October 1962, the ESO Convention was signed in Paris by representatives of Belgium, France, the Federal Republic of Germany, the Netherlands and Sweden. More than a year later, on the 17th of January 1964, the Convention went into effect, following parliamentary ratification in the required majority of countries. In 1967, Denmark also joined. In the early days (partly before the formalities were completed), site surveys were made which led to the choice of La Silla as the observatory location, and work was started on the La Silla infrastructure and on the Schmidt telescope and the 3.6 m telescope. Some other telescopes were ordered from industry. After it was realized that ESO did not have the necessary (technical) management capabilities to bring all its projects to a successful completion, discussions took place with CERN which led in 1970 to the founding of the T(elescope) P(roject) Division in Geneva, partly staffed with CERN personnel. As a result, the 3.6 m telescope was completed in 1976.
1-1 (PDF)
Professor M.K. Vainu Bappu (1927-82)
ADS BibCode:
1982Msngr..30R...1W
Author(s)/Affiliation(s):
West, R. M.
AA(ESO)
Abstract:
It was with great sadness that we received the news of the death, on 19 August 1982, of Professor M.K.V. Bappu, President of the International Astronomical Union and Director of the Indian Institute of Astrophysics, Bangalore, India. Professor Bappu was spending a few months with ESO in Munich, doing research within solar and stellar spectroscopy and at the same time preparing for the XVIIIth IAU General Assembly. A heart ailment necessitated a major surgical intervention, which was apparently successful. Howeyer, post-operative complications set in, and after a heroic struggle, assisted by the foremost medical expertise, Professor Bappu expired in the early evening of 19 August.
2-2 (PDF)
Another Gravitational Lens?
ADS BibCode:
1982Msngr..30....2C
Author(s)/Affiliation(s):
Chen, J. S.; Shaver, P. A.
AA(Peking Observatory and ESO), AB(ESO)
Abstract:
Following the discovery of the Q0957+561 A,B pair and subsequent interpretation as a gravitationally lensed qso, several searches for similar objects have been made, but only two cases have so far been confirmed. In collaboration with astronomers in Edinburgh, one of us (J.-S. Chen) started a qso survey programme two years ago using low-dispersion objective-prism plates taken with the UK Schmidt telescope at Siding Spring Observatory. Three fields have been systematically searched and about 500 qso candidates identified. Among these only one gravitationallens candidate was found. The images (Fig. 1) are ciose together (7"), bright (17.5 mv), stellar, and blue, and the objective-prism spectra contain strong emission lines at very similar redshifts.
3-4 (PDF)
An absorption feature and filamentary structures in the central galaxy of the Centaurus cluster, NGC 4696
ADS BibCode:
1982Msngr..30....3J
Author(s)/Affiliation(s):
Jorgensen, H. E.; Norgaard-Nielsen, H. U.
AA(University Observatory, Copenhagen, Denmark), AB(University Observatory, Copenhagen, Denmark)
Abstract:
Optical features of NGC 4696 observed in 1982 are reported. Blue and red filtered long-interval exposures were made, together with CCD camera observations using filters for redshifted H-alpha + forbidden N II and forbidden S II. A continuum band around 6900 A was detected, together with filaments south and west of the nucleus. Evidence that a reddening absorption feature previously detected was connected to the filamentary structure was found. It is suggested that the object is actually cooling intracluster gas accumulating on the central galaxy of the Centaurus cluster. Future IUE observations will be performed.
4-6 (PDF)
IUE observations of variable Seyfert 1 galaxies
ADS BibCode:
1982Msngr..30....4B
Author(s)/Affiliation(s):
Boisson, C.; Ulrich, M. H.
AA(European Southern Observatory, Garching, West Germany), AB(European Southern Observatory, Garching, West Germany)
Abstract:
IUE spectra of seven known Seyfert galaxies were examined for common features shared with previously observed Seyfert 1 nuclei. The observations were made in the interval 1150-3200 A, with attention given to continuum points when emission or absorption lines, particle events or fiducial events were expected to be missing. Studies were made of NGC 3516, NGC 5548, Akn 120, NGC 3783, NGC 4593, NGC 7213, and ESO 113-IG45(F9). The UV continuum was found to vary in both shape and intensity between different epochs, and a hardening was detected with increasing intensity for all objects. Above 2000 A, the UV continuum in Seyfert spectra was found to be part of the 3000 A bump seen in quasar spectra. Finally, matter was not found to be distributed in the broad line region of Seyferts, where gas having different physical conditions and velocities can be characterized distinctly.
6-9 (PDF)
The variability of RR Tel
ADS BibCode:
1982Msngr..30....6H
Author(s)/Affiliation(s):
Heck, A.; Manfroid, J.
AA(International Ultraviolet Explorer Observatory, Madrid, Spain), AB(Liege, Universite, Cointe-Ougree, Belgium)
Abstract:
Photometric measurements of RR Tel performed at ESO are discussed. RR Tel is a galactic nova which has been associated with a sole outburst, observed in 1944. The photometric observations were made in the ubvy system in August 1981, when a strong brightening was detected in V. IUE data subjected to a Fourier analysis indicate that the object has a period within 5 days of 395 days. Measurements of brightening of the J component also yield a period of 390 days. The presence of a Mira variable is considered, noting the supporting evidence from H2O and TiO spectral bands, but equally the lack of IR data until after 1960. It is suggested that data from before 1944 indicate that modulated bursts of mass transfer and accompanying accretion events preceeded the outburst of the underlying binary star, which could be a link between dwarf novae, classical novae, and symbiotic stars.
9-13 (PDF)
The diffuse interstellar medium and the CES
ADS BibCode:
1982Msngr..30....9F
Author(s)/Affiliation(s):
Ferlet, R.
AA(CNRS, Laboratoire de Physique Stellaire et Planetaire, Verrieres-le-Buisson, Essonne, France)
Abstract:
Techniques for observing and analyzing the characteristics of the interstellar medium are explored. The densities of the gas and dust have been calculated to range from 1/10,000 to 1,000,000 particles/cu cm, with temperatures ranging from 10-1,000,000 K. Most of the atoms are in ground state and are most efficiently observed in terms of resonance absorption lines formed in the spectra of stars beyond them. Most absorption lines reside below 1200 A. The chemical composition of the interstellar medium can be determined by use of the line profiles fitted to theoretical Voigt profiles calculated by varying the parameters of different clouds on the line of sight, i.e., the number of clouds, their radial velocities, the b-values, and the column densities. True abundances can then be obtained by adding the contributions of different elements, then normalizing the abundances to hydrogen. Further discussion is devoted to abundance variations, the galactic halo, and the use of the coude echelle spectrograph. Sample observations of Na I, lithium, and CS(plus) ions are provided.
13-13 (PDF)
List of Preprints Published at ESO Scientific Group
14-15 (PDF)
The Peculiar Ellipsoidal Variable Tu Horologii
ADS BibCode:
1982Msngr..30...14W
Author(s)/Affiliation(s):
Waelkens, C.
AA(Observatoire de Geneve)
Abstract:
The peculiar nature of the lightcurve of the sixth magnitude variable A-type star TU Hor (HR 1081 = HD 21981) was first discovered at ESO by H.W. Duerbeck from Bonn Observatory. In subsequent spectroscopic work in collaboration with A. and J. Surdej, Dr. Duerbeck demonstrated conclusively that TU Hor is a close binary star with an orbital period of about 0.936 days.
15-17 (PDF)
Astronomical Color Printing at ESO
ADS BibCode:
1982Msngr..30...15M
Author(s)/Affiliation(s):
Madsen, C.; Tarenghi, M.
AA(ESO) AB(ESO)
Abstract:
When the photographic labs in the new Garching Headquarters were planned, the installation of a colour lab was also foreseen. Following the removal from Geneva, a market survey of available colour equipment was carried out, leading to the purchase of a Durst 1800 Laborator enlarger featuring a CLS 2000 colour head and a negative carrier able to accommodate 25 x 25 cm originals, an Autopan 40-60 C processing machine and various equipment for process control.
18-20 (PDF)
High dispersion investigation of CP stars around the H-alpha line
ADS BibCode:
1982Msngr..30...18G
Author(s)/Affiliation(s):
Gerbaldi, M.
AA(Institut d'Astrophysique de Paris and Universite de Paris-Sud, Centre d'Orsay)
Abstract:
The determination of the elemental composition of the atmospheres of chemically peculiar (CP) stars by spectroscopic analysis of the H-alpha lines is discussed. CP stars are classified into He-strong, He-weak, Hg-Mn, Bp including the Si 4200 A line, Ap, and metallic line stars. The atmospheres of CP stars are slowly rotating and have a magnetic field. The H-alpha profile of the He-weak star HD 90264, a double-line spectroscopic binary, has indicated that the slow rotation is due to a tidal interaction between the stars, a feature which is not probable for CP stars. HD 92064 was found to be a spectral type B5 or B6V from ubvy analysis. H-alpha observations indicate an effective temperature of 17,000 K for both stars, which have similar mass and luminosity. Further studies with coude spectrographs are recommended to determine if HD 90264 is in fact a CP star.
21-21 (PDF)
Near Infrared Photometry of Protostars
ADS BibCode:
1982Msngr..30...21F
Author(s)/Affiliation(s):
Fridlund, C. V. M.
AA(Stockholm Observatory)
Abstract:
For several years our group at Stockholm Observatory has been involved in a far infrared study 0f star-forming regions. This project, which is performed in collaboration with the University of Groningen in the Netherlands, consists of mapping molecular clouds, where we have indications of star formation, with a two-channel photometer. The photometer is fed by a 60 cm telescope which is carried to 35 km altitude by a helium-lilled balloon. The two channels of the photometer are sensitive between 60 and 200 microns. In the clouds we are studying there are objects strongly believed to be protostars. These stars heat up the dust surrounding them, and the dust then reemits the stellar radiation at far-infrared wavelengths. In this way we can study this type 01 very young objects although they are totally obscured in the visual part of the spectrum. We have studied several objects in which known near-infrared (1 to 5 microns) sources are Iying. In fact we used the existence 0f near-infrared sources as one 0f our indicators for on-going star formation. The balloon data made it possible to assign an accurate total luminosity to each 0f these sources.
References:
D. Engels, W.A. Sherwood, W. Wamsteker and G.V. Schultz, ESO Preprint No. 130, 1980.
; K.M. Strom, S.E. Strom and F.J. Vrba, A.J. 81,320,1976.
; M. Cohen and R.D. Schwartz, Ap.J. 233, L77, 1979.
; M. Cohen, Ap.J. 185, L75, 1973.
; DA Allen, Ap.J. 172, L55, 1972.
21-22 (PDF)
A new infrared telescope.
ADS BibCode:
1982Msngr..30...21P
Author(s)/Affiliation(s):
Pacini, F.
AA(Osservatorio di Arcetri)
Abstract:
An important facility for Italian astronomy has been formally inaugurated on October 15, 1982 with the presence 0f the President of the National Research Council, E. Quagliariello, the Director General 0f ESO, L. Woltjer, H. Debruner on behalf 0f the Hochalpine Forschungs-Stationen and various other Italian and Swiss authorities. The new 1.5 m Cassegrain telescope is located on the Gornergrat (3,150 meters). The site can be easily reached from Zermatt by train under almost any seasonal condition. This point was proven on the day of the ceremony when an intense, early-fall snow storm amused and shocked some participants, at least those coming from sunny Italy!
22-22 (PDF)
Personnel Movements
23-26 (PDF)
Digital speckle interferometry of Juno, Amphitrite and Pluto's moon Charon
ADS BibCode:
1982Msngr..30...23B
Author(s)/Affiliation(s):
Baier, G.; Hetterich, N.; Weigelt, G.
AA(Physikalisches Institut der Universität Erlangen,Fed. Rep. of Germany), AB(Physikalisches Institut der Universität Erlangen,Fed. Rep. of Germany), AC(Physikalisches Institut der Universität Erlangen,Fed. Rep. of Germany)
Abstract:
Digital speckle interferometric observations of the 9th and 11th magnitude asteroids Juno and Amphitrite and of the 16th magnitude moon of Pluto, Charon, are reported. Results are also reported for the 11th magnitude Seyfert galaxy NGC 1068, the 12.7th magnitude quasar 3 C 273, and the 16.2 magnitude triple QSO PG 1115+080. The observational technique consists of Fourier analyses of large numbers of short-exposure photographs, i.e., speckle interferograms, to produce high resolution autocorrelated imagery. Short exposures are used to retain high resolution features. Image intensifiers with a gain of 300,000 were part of the equipment, together with a photon-counting mode capability. A total of 1450 speckle interferograms were produced for Juno, 1776 for Amphitrite, and 15,000 for Charon. A method for image reconstruction involving speckle masking is described, together with high resolution speckle spectroscopy.
26-28 (PDF)
The CCD on La-Silla
ADS BibCode:
1982Msngr..30...26P
Author(s)/Affiliation(s):
Pedersen, H.; Cullum, M.
AA(ESO) AB(ESO)
Abstract:
Throughout the history of observational astronomy, there has been a continual demand for detectors of higher sensitivity and lower noise. The ultimate goal, of course, is for an imaging detector that will record every photon reaching it with a noise level limited only by the random fluctuations of the photons themselves. Although we may not yet have the ideal detector, there has been a quiet revolution taking place in astronomy over the last year or so which has caused the world's major observatories to replace many of their older detectors, such as image intensifiers, by Charge-Coupled Oevices (or CCOs as they are universally known).
28-30 (PDF)
The Distance of the Magellanic Clouds
ADS BibCode:
1982Msngr..30...28D
Author(s)/Affiliation(s):
Divan, L.
AA(Institut d'Astrophysique, Paris)
Abstract:
The Magellanic Clouds are very important for many problems of Astrophysics. At a distance of about one tenth of that of the Andromeda Nebula, they are the nearest extragalactic objets, and in many cases the individual stars can be studied in detail. On the other hand, the distance to each Cloud is quite large when compared to the linear dimensions. No distance effect greater than ± 0.15 mag is to be expected on the apparent magnitudes and, practically, all objects can be considered to be at the same distance. A great advantage of the Magellanic Clouds over other groups of stars is that their population, with radial velocities around + 275 km/s for the Large Cloud and + 160 km/s for the Small Cloud, can easily be separated from the Galactic foreground stars. In addition, very little interstellar absorption occurs along the line of sight, either in the Galaxy or in the Clouds. For all these reasons the Magellanic Clouds are a very efficient tool (c.f. the discovery of the period-luminosity relation in the SMC as early as 1904) and considerable efforts have been made to determine theirdistances
31-32 (PDF)
Algunos Resumenes
31-31 (PDF)
Latest News
31-31 (PDF)
Dome for the 2.2m Telescope Commissioned
ADS BibCode:
1982Msngr..30...31B
Author(s)/Affiliation(s):
Bauersachs, W.
AA(ESO)
Abstract:
It took the American crew of Observa Dome Lab. (Jackson, Mississippi) sjx weeks to install the dome at the 2.2 m telescope site on La Silla. In spite of heavy winds and unfriendly weather during the first weeks, the work was completed ahead of schedule on November 20, 1982.