ISSN:0004-6337    

DOI:10.1002/asna.2113050202

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractA complex of 11 objects with a surface brightness of about 26 mag/□” is detected in the direction of the M81 group of galaxies. The argumentes are presented in favour of the fact that they are at the distance of the M81 group; their linear diameters (2 to 3 kpc) and absolute magnitudes (MB= ‐11mto ‐12m) are in agreement with the parameters of the known dwarf galaxies of the Local group. An assumption about the tidal stability of the complex of dwarfs relative to M81 gives an estimation of its summary mass ≳ 1 · 108M⊙ and of its mass‐to‐luminosity ratio ℜ/L≳ 1.

ISSN:0004-6337    

DOI:10.1002/asna.2113050203

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113050204

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractThe main photometric parameters of six very low surface brightness dwarf galaxies of the M81 group are obtained. For the first time the luminosity profiles of extreme dwarfs outside the local group are given. The profiles are much more consistent to the exponential law than to ther1/4 law. No significant differences in profile between irregulars and sphericals could be found.

ISSN:0004-6337    

DOI:10.1002/asna.2113050205

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113050206

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractAusgehend vom Becklin‐Neugebauer‐Objekt in der Orion‐Molekülwolke I als Prototyp wird anhand zahlreicher Beobachtungsmerkmale eine Klasse von kompakten Infrarotquellen abgegrenzt, von denen man annehmen kann, daß sie junge massereiche von optisch dicken Staubhüllen umgebene Sterne sind. Ein Katalog gibt für 34 Objekte ausführliche Informationen, u. a. über Infrarot‐ und Radiospektren, das Vorhandensein von Masern und Ausströmung

ISSN:0004-6337    

DOI:10.1002/asna.2113050207

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractSpectroscopic and photometric observations of the variable ET And were carried out in the years 1981/82. In addition to the known periodical variation of the radial velocities of 48.308 days produced by a companion and the photometric period of 1.61883 days probaly resulting from the rotation of the star some other periodical variations exist. The radial velocities vary further with a period of 0.1989 days and the photometric data with the half of this value, i.e. with 0.0994 days. The minima of the light coincide with the extrema of the radial velocity. The radial velocity curve deviates somewhat from a pure harmonic, more precisely, the values increase more rapidly than they decrease. The same behaviour also appears for the corresponding part in the light curve.

ISSN:0004-6337    

DOI:10.1002/asna.2113050208

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractThe periodic comet Wild 3 had in May 1977 a close encounter with Jupiter. The motion and magnitudes of Wild 3 before and after this event are examined.

ISSN:0004-6337    

DOI:10.1002/asna.2113050209

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractFor the determination of positions and proper motions of celestial objects until now only corrections of errors caused by the instrument and by the atmosphere have been carried out. Errors of measurement as random errors have not been considered. Therefore a Monte Carlo simulation of the propagation of these random errors in the calculation of the so‐called averaged measurement coordinates and the proper motions were undertaken. As a typical quantity, the corresponding standard deviation was estimated, and its dependence on occuring parameters was studied. With this method, the true values of the considered quantities are known (generated by simulation) so that the errors of the calculated quantities can be directly determined. Inferences to the accuracy of a single measurement were mad

ISSN:0004-6337    

DOI:10.1002/asna.2113050210

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

Abstract151 positions of 32 minor planets found on plates taken from 1979 to 1983 with the astrograph 400/1950 mm of Sonneberg Observatory are given.

ISSN:0004-6337    

DOI:10.1002/asna.2113050211

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY