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Mesures et decouvertes d'etoiles doubles effectuees a la lunette de 50cm de l'Observatoire de Nice. Measures and discoveries of visual double stars made with the 50cm refractor at the Nice Observatory.
Measures and discoveries of visual double stars made at the Observatoirede la Cote d'Azur at Nice, between 1988 and 1994, with the 50cmrefractor equipped with a filar micrometer and electronic recordingdevice. The programs proposed by J. Dommanget involve the complement ofthe C.C.D.M. (resolving problems of identification of double stars andof coherency in the Index) and the INput CAtalog Hipparcos (resolutionof ambiguities on the binarity and on the position of certain doublestars which have seldom or never been observed again from the epoch ortheir discovery). The author has discovered three new binaries: JCT1,JCT2 and JCT3.
| A preliminary compilation of DS-programme star positions
A catalog is presented of the double-star-program (DS-program) starpositions, listing right ascensions for 930 DSs and declinations for1225 DSs of the program. The positions were compiled from the observedvalues obtained between 1980 and 1987 with the meridian circles of sixUSSR observatories (the Moscow, Kazan', Kiev, Khar'kov, Odessa, andTashkent Observatories) and the Belgrade Observatory. The measurementsand the treatment of the observational material were performed using therelative method, and the FK-4 system stars were used as reference stars.
| The rotation of horizontal-branch stars. II - Members of the globular clusters M3, M5, and M13
Broadened lines evident in echelle spectra obtained at the MultipleMirror Telescope suggest that rotation at a level of v sin i greaterthan 15 km/s is present in seven of 17 horizontal-branch (HB) starsbelonging to the globular clusters M3, M5, and M13. The maximum size ofthe broadening, corresponding to v sin i approximately 30 km/s,resembles that seen in field HB stars. Radial velocities and clusterdensities mitigate against binary association as its cause. Instead, thediscovery implies the presence of internal rotation among themain-sequence members of at least some globular clusters; this affectsthe lifetime on the main sequence and therefore the age attributed tothe cluster from a comparison of the color of the main-sequence turnoffwith stellar evolutionary calculations. Indeed, since the high frequencyand the large values of rotation found in M13 stars are distinctlydifferent from what is observed in other clusters and the field, thiswork supports the idea that the anomalously blue horizontal branch ofM13, and the large star-to-star variations in carbon and nitrogenabundances seen among its low-luminosity giants, might be due to a morefrequent occurrence of larger stellar rotational velocities.
| Mesures d'etoiles doubles faites a Nice.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...33..275M&db_key=AST
| Positions moyennes et mouvements propres de 355 etoiles DU GC de la zone de declinaison +33 +36.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...26..219M&db_key=AST
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | פרסאוס |
| התרוממות ימנית: | 03h08m45.91s |
| סירוב: | +35°27'31.1" |
| גודל גלוי: | 7.789 |
| מרחק: | 149.254 פארסק |
| תנועה נכונה: | 32.3 |
| תנועה נכונה: | -48.1 |
| B-T magnitude: | 7.966 |
| V-T magnitude: | 7.804 |
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