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HD 168302


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Diffuse interstellar bands in RAVE survey spectra
We have used spectra of hot stars from the RAVE Survey in order toinvestigate the visibility and properties of five diffuse interstellarbands previously reported in the literature. The RAVE spectroscopicsurvey for Galactic structure and kinematics records CCD spectracovering the 8400-8800 Å wavelength region at 7500 resolvingpower. The spectra are obtained with the UK Schmidt at the AAO, equippedwith the 6dF multi-fiber positioner. The DIB at 8620.4 Å is by farthe strongest and cleanest of all DIBs occurring within the RAVEwavelength range, with no interference by underlying absorption stellarlines in hot stars. It correlates so tightly with reddening that itturns out to be a reliable tool to measure it, following the relationEB-V = 2.72 (± 0.03)× EW~(Å), validthroughout the general interstellar medium of our Galaxy. The presenceof a DIB at 8648 Å is confirmed. Its intensity appears unrelatedto reddening, in agreement with scanty and preliminary reports availablein the literature, and its measurability is strongly compromised bysevere blending with underlying stellar He I doublet at 8649 Å.The two weak DIBs at 8531 and 8572 Å do not appear real and shouldactually be blends of underlying stellar lines. The very weak DIB at8439 Å cannot be resolved within the profile of the much strongerunderlying hydrogen Paschen 18 stellar line.Table 1 is only available in electronic form at http://www.aanda.org

Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.

An Einstein Observatory SAO-based catalog of B-type stars
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.

Empirical temperature calibrations for early-type stars
Three temperature calibrations of suitable photometric quantities havebeen derived for O and B stars. A sample of 120 stars with reliableT(eff.) determinations has been used for establishing each calibration.The different calibrations have been critically discussed and compared.Temperature determinations for 1009 program stars have been obtainedwith an accuracy of the order of 10 percent.

E(B-V) determination from an UV-visual two-colour diagram - O and B stars in the Catalogue of Stellar Ultraviolet Fluxes
For the O and B type stars in the Catalogue of Stellar UltravioletFluxes, an approach is presented which does not require a preciseknowledge of spectral type and luminosity class for deriving E(B-V)color excesses. The method is based on the use of an UV-visual two-colordiagram; galactic variations in the interstellar extinction law areanalyzed and fully taken into account. The results have been comparedwith those derived by using the differences between observed andintrinsic colors for stars with known spectral classification. The verygood agreement in a large number of cases (94 percent) demonstrates thatthe present approach permits the derivation of reliable color excessvalues for early-type stars even if only a rough spectral classificationis available.

UBV photometry of the stars in the fields of emission Nebulae. II - M 17
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASJ...28...35O&db_key=AST

On the kinematical and spatial coincidence of optical and radio spiral arms in our galaxy.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....24..393M&db_key=AST

A Test for Relative Motions of Gas and Young Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..273M&db_key=AST

Scanner Observations of λ 4430
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966ApJ...144..921W&db_key=AST

A study of the region of M 17 at a wavelength of 3.75 cm.
Not Available

A Catalogue of H II Regions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJS....4..257S&db_key=AST

A Catalogue of Emission Nebulae Near the Galactic Plane.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1953ApJ...118..362S&db_key=AST

Polarization of Stellar Radiation. III. The Polarization of 841 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...114..241H&db_key=AST

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Osservazione e dati astrometrici

Costellazione:Sagittario
Ascensione retta:18h19m39.42s
Declinazione:-16°01'20.3"
Magnitudine apparente:9.341
Moto proprio RA:1.9
Moto proprio Dec:-2.5
B-T magnitude:9.456
V-T magnitude:9.351

Cataloghi e designazioni:
Nomi esatti   (Edit)
HD 1989HD 168302
TYCHO-2 2000TYC 6265-615-1
USNO-A2.0USNO-A2 0675-25041663
HIPHIP 89804

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