Anatomical identifications of stars: Textual descriptions in Ptolemy's star catalogue

The catalogue is divided into three sections: bright stars with magnitudes less than or equal to 6.7: other stars having numbers in the Smithsonian Astrophysical Star Catalogue with magnitudes greater than 6.7: and other stars with no SAO numbers, usually faint and with often only fragmentary information concerning their magnitudes or spectra.Each section has the following columns: SAO number, other name, magnitude, spectral type, run number of the observation, date in obvious coded form, grade — grade zero indicates no duplicity, grade 1 possible duplicity, grade 2 probable duplicity, and grade 3 certain duplicity. Grades are based on statements by observers. For grades other than zero the vector separation and its computed error are given in arc milliseconds. P.A. denotes the direction in which the vector separation is measured, that is the position angle on the lunar limb as modified by the slope deduced in favorable cases from the spacing of the diffraction bands on the occultation trace. The next column gives the limb slope and its error.

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Statistics of Multiple Stars: Some Clues to Formation Mechanisms

Symposium - International Astronomical Union ◽

10.1017/s0074180900225096 ◽

2001 ◽

Vol 200 ◽

pp. 84-92 ◽

Cited By ~ 9

Author(s):

Andrei Tokovinin

Keyword(s):

Observational Studies ◽

Binary Systems ◽

Close Binaries ◽

Formation Mechanisms ◽

Tidal Dissipation ◽

Multiple Star ◽

Star Catalogue ◽

Multiple Stars ◽

Available Information ◽

Average Angle

The available information on the statistics of high multiplicity (3–6 components) systems is reviewed. The ratio of triple to binary systems is f3 ≍ 0.11, while fn ≍ 0.25 for higher n. Despite selection effects in the multiple star catalogue, the signatures of formation mechanisms are found in the distributions of period ratios and mass ratios. For example, the frequent occurrence of close sub-systems with periods less than 6 days can be explained by tidal dissipation in a 3-body system. In triple stars the angular momentum vectors of inner orbits are inclined to those of outer orbits by an average angle of 50°, hence the orbital spins are neither co-aligned nor completely random. Close binaries have a tendency to be found in higher-multiplicity systems, showing that close and wide binarity is statistically related. Future theoretical and observational studies are outlined.

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Astrometric Positions of Quasars by CCD Observations

International Astronomical Union Colloquium ◽

10.1017/s0252921100047096 ◽

1997 ◽

Vol 165 ◽

pp. 547-550

Author(s):

M. Assafin ◽

R. Vieira Martins ◽

A.H. Andrei

Keyword(s):

Reference System ◽

Star Catalogue ◽

Sky Survey ◽

Ccd Observations ◽

Guide Star ◽

Celestial Reference System

AbstractWe present results of CCD observations for 85 quasars with −80° ≤ δ ≤ +20° declination, belonging to the International Celestial Reference System (ICRS). The positions are referred to the Carlsberg Series (CAMC) and PPM catalogues. We discuss a method which allows one to obtain precise positions based only on CCD observations, on the use of the Digitized Sky Survey of ST ScI and on the Guide Star Catalogue. The results are compared with the VLBI positions.

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The Second Guide Star Catalogue

Symposium - International Astronomical Union ◽

10.1017/s0074180900129225 ◽

1998 ◽

Vol 179 ◽

pp. 431-432 ◽

Cited By ~ 8

Author(s):

B. McLean ◽

G. Hawkins ◽

A. Spagna ◽

M. Lattanzi ◽

B. Lasker ◽

...

Keyword(s):

Adaptive Optics ◽

New Technology ◽

Great Success ◽

Next Generation ◽

Large Aperture ◽

Star Catalogue ◽

Queue Scheduling ◽

Natural Data ◽

Data Source ◽

Guide Star

Although the HST GSC–I (Paper-I: Lasker et al. 1990, Paper-II: Russell et al. 1990, Paper-III: Jenkner et al. 1990) has been used with great success operationally, it was always known that it was possible to improve the scientific and operational usefulness by an increase in scope to include multi-color and multi-epoch data. Once the GSC-II concept was established, it was evident that, even beyond the original motivations in HST operations, it would address a number of other astronomical needs such as increasing demands for fainter catalogues to support remote or queue scheduling capabilities and adaptive optics on the next generation of large-aperture, new-technology telescopes. In addition, the all sky nature of the GSC–II makes it a natural data source for research in galactic structure.

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Systematic Differences Instrument Minus FK5 in the Southern Hemisphere

Symposium - International Astronomical Union ◽

10.1017/s0074180900087118 ◽

1990 ◽

Vol 141 ◽

pp. 385-386

Author(s):

G. Carrasco ◽

P. Loyola

Keyword(s):

Southern Hemisphere ◽

Astronomical Observatory ◽

Reference Star ◽

Meridian Circle ◽

Proper Motions ◽

Faint Star ◽

International Reference ◽

Star Catalogue

Observations of Fundamental Faint Star Catalogue (FKSZ) stars, made with the Repsold Meridian Circle at Cerro Calán National Astronomical Observatory, began in 1979 and finished in 1988. Today International Reference Star (IRS) observations are in progress. These observations correspond to the second epoch of the Santiago 67 Catalogue (Carrasco and Loyola 1981) and they are going to be used for determining the proper motions of these stars.

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Complex Geodynamical Investigations in the Area of the USSR Academy of Sciences Central Astronomical Observatory at Pulkovo

Symposium - International Astronomical Union ◽

10.1017/s0074180900086228 ◽

1990 ◽

Vol 141 ◽

pp. 72-72

Author(s):

V. K. Abalakin ◽

V. I. Bogdanov ◽

Yu.D. Boulanger ◽

V. A. Naumov

Keyword(s):

Coordinate System ◽

Ussr Academy ◽

Astronomical Observatory ◽

Coordinate Systems ◽

Inertial Coordinate System ◽

Gravitation Field ◽

Practical Applications ◽

Star Catalogue ◽

Academy Of Sciences

For astronomical, geodetical and geodynamical investigations as well as for practical applications the inertial coordinate system is widely used which is based on the Fundamental Star Catalogue FK5 together with local coordinate systems in observation stations on the Earth's surface which are intrinsically connected with the geometry of the gravitation field.

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A Galactic Lane with Low Absorption

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000010778 ◽

1968 ◽

Vol 1 (3) ◽

pp. 92-93 ◽

Cited By ~ 4

Author(s):

G. Lyngå

Keyword(s):

Photometric Data ◽

Ob Stars ◽

Star Catalogue

In Table I are given photometric data and spectral classes for some OB stars in galactic longitudes 298°-306°. The data have been obtained using a photoelectric photometer on the Reynolds reflector and the Meinel spectrograph on the 100 cm reflector at Siding Spring. Numbers refer to an OB star catalogue in preparation.

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Galactic Distribution, Kinematics, Locations in Clusters and H-R Diagrams, and Duplicity of Be Stars (Review Paper)

International Astronomical Union Colloquium ◽

10.1017/s0252921100116653 ◽

1987 ◽

Vol 92 ◽

pp. 470-485 ◽

Cited By ~ 1

Author(s):

Helmut A. Abt

Keyword(s):

Be Stars ◽

Orbital Elements ◽

Constant Frequency ◽

B Stars ◽

Star Catalogue ◽

Solar Motion ◽

Observational Techniques ◽

Mass Functions ◽

Galactic Distribution ◽

Contraction Stage

AbstractThe locations of 143 B0e-B7e III-V stars listed in the Bright Star Catalogue are similar to those of the early-B Gould Belt stars. Therefore the Be stars have roughly the same ages and origins as early B stars. The frequency of runaway Be stars must be less than several percent. The radial velocities of Be stars show primarily the reflex of solar motion and show no evidence for systematically negative velocities attributable to mass-loss effects upon the absorption profiles. The scatter in the residual velocities is such that there is unlikely to be many undetected binaries with orbital amplitudes greater than 10 km s-l. We are unable to state whether or not Be stars tend to occur during the overall contraction stage, but we do observe Be stars in roughly constant frequency in clusters of all ages. About 18% of the field B0-B7 III-V stars are Be stars. Clusters show both lower and higher frequencies that may be real or may be due to different observational techniques. The frequencies and distribution of binary periods for Be stars is the same as for non-emission B stars except for the lack of periods less than 10-1 yr. Statistically the 12 classical Be stars with known orbital elements have mass functions indicating that their secondaries are more massive than neutron stars and their secondary mass distribution is like that of normal B stars. We observe 35 companions for 100 Be primaries, so after correction for undetected companions, it seems likely that most Be stars have companions, mostly with periods of years.

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