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HD 117478


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Kinematics of Hipparcos Visual Binaries. II. Stars with Ground-Based Orbital Solutions
This paper continues kinematical investigations of the Hipparcos visualbinaries with known orbits. A sample, consisting of 804 binary systemswith orbital elements determined from ground-based observations, isselected. The mean relative error of their parallaxes is about 12% andthe mean relative error of proper motions is about 4%. However, even 41%of the sample stars lack radial velocity measurements. The computedGalactic velocity components and other kinematical parameters are usedto divide the stars with known radial velocities into kinematical agegroups. The majority (92%) of binaries from the sample are thin diskstars, 7.6% have thick disk kinematics and only two binaries have halokinematics. Among them, the long-period variable Mira Ceti has a verydiscordant {Hipparcos} and ground-based parallax values. From the wholesample, 60 stars are ascribed to the thick disk and halo population.There is an urgent need to increase the number of the identified halobinaries with known orbits and substantially improve the situation withradial velocity data for stars with known orbits.

Observations of Double Stars. XVIII.
Micrometer observations of 1350 pairs in 1995-1997 are listed.

Observations of double stars and new pairs. XIV
Results of a continuing survey of visual double stars are presented,including 4880 measurements made from February 1987 to November 1989.The positions in WDS format and Durchmusterung numbers are given for 194pairs first reported here. Micrometer measurements of 1142 doubles madewith the Swarthmore 61 cm refractor are presented. Magnitudes areestimated for some of the objects. Plate measurements, plateorientations, position angles, number of nights, and measured exposuresare given. Visual observations of 342 pairs obtained in May 1989 atCerro Tololo, mostly with the 1.0 m reflector, are reported.

About some enigmatic binary stars
Observational data concerning six binary star systems which displaycontradictory or paradoxical characteristics are reviewed. Attention isgiven to ADS 8590 - HU 571, ADS 8762 HU 642, ADS 8926 - A 1789, ADS10007 - A 225, ADS 11344 - HU 66, and ADS 11698 - BU 971. Thepossibility that the controversies are due to experimental error isdiscussed and discounted, due to the reproducibility of the positions,magnitudes, and the separations of the components of the binaries.

Micrometer observations of double stars.8.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJS...29..315H&db_key=AST

Measures of 278 double stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1962AJ.....67..403W&db_key=AST

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Dades d'Observació i Astrometria

Constel·lació:Virgo
Ascensió Recta:13h30m29.63s
Declinació:+07°29'09.8"
Magnitud Aparent:8.425
Distancia:167.224 parsecs
Moviment propi RA:11.5
Moviment propi Dec:-29.5
B-T magnitude:8.858
V-T magnitude:8.461

Catàlegs i designacions:
Noms Propis   (Edit)
HD 1989HD 117478
TYCHO-2 2000TYC 313-1267-1
USNO-A2.0USNO-A2 0900-07407409
HIPHIP 65897

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