ADS BibCode:
1980Msngr..21....1C
Author(s)/Affiliation(s):
Cayrel, R.
AA(director of the Corporation)
Abstract:
The 3.6 m telescope of the Canada-France-Hawaii Corporation on the summit of Mauna Kea, on one of the Hawaiian islands, was put into operation last March. This nice instrument, located on what seems to be one of the best possible sites in the world, is presented to the readers of the Messenger by Dr. Roger Cayrel, director of the Corporation.

ADS BibCode:
1980Msngr..21....4M
Author(s)/Affiliation(s):
Macchetto, F.
AA(ESA, ESTEC, Noordwijk)
Abstract:
The phenomenon of mass-Ioss in hot stars has been known for a good many years. The strong stellar winds which are the manifestation of this phenomenon are observed as broad emission lines in the spectra of hot stars. In a number of cases the emission is red-shifted from the laboratory wavelength and a blue shifted absorption component appears; this is the so-calied "P-Cygni" line profile as it was first seen in the spectrum of the star P Cygni.

ADS BibCode:
1980Msngr..21....6.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21....7D
Author(s)/Affiliation(s):
Danziger, I. J.; D'Odorico, S.; Goss, W. M.
AA(ESO) AB(ESO) AC(Kapteyn Astronomical Institute, Groningen)
Abstract:
The discovery of the first supernova remnants in M33 was made on material from a medium-size telescape but the subsequent detailed investigation involved the use of same of the largest optical and radio astronomy facilities in the world. Eventually, a complete study of these objects will improve our understanding of the stellar population and of the interstellar medium of that galaxy.

ADS BibCode:
1980Msngr..21...11F
Author(s)/Affiliation(s):
Fosbury, R. A. E.
AA(Royal Greenwich Observatory (previously ESO))
Abstract:
It appears that only ellipticals become powerful radio galaxies. We believe this to be due to the depth of the gravitational potential weil and the characteristic paucity of interstellar material in these galaxies. Aside from the particular interest of the nuclear activity associated with the radio galaxy phenomenon, these objects may, in two rather distinct ways, give us very useful information about the intergalactic medium in a range of different environments.

ADS BibCode:
1980Msngr..21...14.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21...15.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21...16R
Author(s)/Affiliation(s):
Ritter, H.
AA(Max Planck Institute for Physics and Astrophysics, Garehing)
Abstract:
Cataclysmic variables (CV's) is the common name of a subgroup of eruptive variables consisting of the classical novae, the dwarf novae, the recurrent novae and of the nova-like objects. Since Kraft's pioneering investigation about twenty years aga (Kraft, R. P.: 1973, Adv. Astron. Astrophys. 2, 43) we know that probably all of the CV's are close binaries. However among the roughly 500 CV's known at present, only for about 50 objects has the bi nary nature been established by observations. Hereafter these objects will be referred to as cataclysmic binaries (CB's). From the histogram of their orbital periods, shown in Fig. 1, it is seen that CB's have extremely short orbital periods, typically only a few hours. Moreover the histogram shows a remarkable gap of orbital periods in the range between about 2 and 3 hours. This gap has been found to be statistically highly significant. Apparently CB's are divided into two subgroups, i. e. into the ultrashort- period CB's (hereafter USPCB's) with orbital periods P <= 2h and into the longer-period CB's (hereafter LPCB's) with orbital periods P >= 3h

ADS BibCode:
1980Msngr..21...16.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21...18S
Author(s)/Affiliation(s):
Sellwood, J.
AA(ESO)

ADS BibCode:
1980Msngr..21...19R
Author(s)/Affiliation(s):
Richter, W.
AA(ESO)
Abstract:
As an intermediate step towards a very large telescope (VLT), ESO intends to design and to build a New Technology Telescope (NTT) with a mirror of 3.5 m diameter. This telescope will help on the one hand to reduce the demand of the 3.6 m telescope on La Silla and will allow on the other hand to test some of the new ideas for telescope design in practice.

ADS BibCode:
1980Msngr..21...20G
Author(s)/Affiliation(s):
Gillespie, A. R.
AA(Max Planck Institute for Radio Astronomy, Bonn)
Abstract:
Ouring the last few years optical astronomers have been surprised to find radio astronomers using the larger optical telescopes with equipment that they have brought with them. The objects studied are usually molecular clouds and are observed using radio frequency transitions of carbon monoxide. In this article, Or. A. R. Gillespie from the Max Planck Institute for Radio Astronomy in Bonn gives an outline of the astronomy that is produced as weil as some of the results that have come from optical telescopes used in this way.

ADS BibCode:
1980Msngr..21...23.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21...24.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1980Msngr..21...25A
Author(s)/Affiliation(s):
Arp, H.
AA(ESO Scientific Group in Geneva)
Abstract:
Dr. Halton Arp from Mt. Wilson and Las Campanas Observatory has spent a few months with the ESO Scientific Group in Geneva. He is weil known for his unconventional ideas about the origin of the redshift of quasars; however, surprisingly, he has chosen to write on a "harmless" subject: dwarf galaxies.
References:
Arp, H. 1978, Ap. J., 220,401.

ADS BibCode:
1980Msngr..21...27S
Author(s)/Affiliation(s):
Sellwood, J.
AA(ESO)
Abstract:
We may be accustomed to believing that most problems confronting us in astronomy involve difficult and exotic physics. In this article, I would like to draw attention to a problem, as yet unsolved, posed by some of the simplest laws of physics known, viz: Newton's law of gravity and his laws of motion. To take a familiar example, we know that these laws give a pretty good description of the motion of the planets on their orbits about the sun; even though Einstein's refinements were required to account for some very minor discrepancies.

ADS BibCode:
1980Msngr..21...29D
Author(s)/Affiliation(s):
Dennefeld, M.; Materne, J.
AA(Technische Universität, Berlin) AB(Technische Universität, Berlin)
Abstract:
Among the 338 exotic, intriguing and/or fascinating objects contained in Arp's catalogue of peculiar galaxies, two, Arp 146 and 147, are calling special attention as a presumably separate class of objects displaying closed rings with almost empty interior. It is difficult to find out when, historically speaking, attention was called first to this type of object as a peculiar class, but certainly ga1axies with rings were widely found and recognized in the early sixties, ul}der others by Vorontsov-Velyaminov (1960), Sandage (1961) in the Hubble Atlas or de Vaucouleurs (1964) in the first reference catalogue of ga1axies. The most recent estimates by Arp and Madore (1977) from a search on about 200 Schmidt plates covering 7,000 square degrees give 3.6 per cent of ring galaxies among 2,784 peculiar galaxies found. However, despite the mythological perfection associated with a circle, some ordering is necessary before trying to understand the nature of such objects. This is particularly true because a large fraction of those galaxies with rings are probably normal spiral galaxies of type RS or S(r) as defined by de Vaucouleurs, where the spiral arms are simply "closing the circle". A good example of such "ordinary" galaxy is NGC 3081 in the Hubble Atlas .
References:
Arp, H. and Madore, B. F. 1977, Q. J. Roy.Astr. Soc., 18, 234.
Oennefeld, M., Laustsen, S. and Materne, J. 1979, Astron. Astroph., 74, 123.
Fosbury, R. A. E. and Hawarden, T. G. 1977, Mon.Not.R.Astr.Soc., 178,473.
Freeman, K. C. and de Vaucouleurs, G. 1974, Ap.J., 194,569.
Lynds, R. and Toomre, A. 1976, Ap.J., 209,382.
Sandage, A., The Hubble Atlas of Galaxies, 1961.
Theys, J. C. and Spiegel, E. A. 1976, Ap.J., 208,650.
Theys, J. C. and Spiegel, E. A. 1977, Ap.J., 212,616.
de Vaucouleurs, G. and de Vaucouleurs, A. 1964, The Reference Catalogue of Bright Galaxies.
Vorontsov-Velyaminov, B. A. 1960, Sov.Astron., 4, 365.

ADS BibCode:
1980Msngr..21...32.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
Como ya se mencion6 en "EI Mensajero" No. 20, se espera que Italia y Suiza se integren a ESO como paises miembros a partir de 1981.