Observations of Star-Forming Regions with the Midcourse Space Experiment
We have imaged seven nearby star-forming regions, the Rosette Nebula,the Orion Nebula, W3, the Pleiades, G300.2-16.8, S263, and G159.6-18.5,with the Spatial Infrared Imaging Telescope on the Midcourse SpaceExperiment (MSX) satellite at 18" resolution at 8.3, 12.1, 14.7, and21.3 μm. The large angular scale of the regions imaged (~7.2-50deg2) makes these data unique in terms of the combination ofsize and resolution. In addition to the star-forming regions, twocirrus-free fields (MSXBG 160 and MSXBG 161) and a field near the southGalactic pole (MSXBG 239) were also imaged. Point sources have beenextracted from each region, resulting in the identification over 500 newsources (i.e., no identified counterparts at other wavelengths), as wellas over 1300 with prior identifications. The extended emission from thestar-forming regions is described, and prominent structures areidentified, particularly in W3 and Orion. The Rosette Nebula isdiscussed in detail. The bulk of the mid-infrared emission is consistentwith that of photon-dominated regions, including the elephant trunkcomplex. The central clump, however, and a line of site toward thenorthern edge of the cavity show significantly redder colors than therest of the Rosette complex.
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The Pleiades, Map-based Trigonometric Parallaxes of Open Clusters. V.
The Multichannel Astrometric Photometer and Thaw Refractor (Thaw/MAP) ofthe University of Pittsburgh's Allegheny Observatory have been used todetermine the trigonometric parallax of the Pleiades star cluster. Theparallax determined, 0.00764" with a standard error of +/-0.00043"(corresponding to a distance modulus of 5.59+/-0.12 mag) places thecluster significantly further away than indicated by the mean parallaxof cluster members drawn from the Hipparcos catalog. The distancederived here is in general agreement with values based on main-sequencefitting, indicating that cluster members are not subluminous assuggested by the Hipparcos-based results. The current study combines thedata from our initial study of this cluster with new observations ofthat region and of a second Pleiades region in an overlappingconfiguration. It thus supersedes our first determination of theparallax of the Pleiades cluster. A third Pleiades field is beingselected for future measurement of the cluster's trigonometric parallax,and assistance with the luminosity classification of reference stars issought.
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Measurements of double stars 1993.67 - 1998.13
624 Micrometer Measurements of 224 pairs with a 32.5 cm Cassegrain, 719Measurements of 310 double stars with a 360 mm Newtonian are given.Tables 1 to 4 are available in electronic form only at the CDS130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html
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The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
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ICCD speckle observations of binary stars: Measurements during 1994-1995
We present speckle observations of nineteen double stars and the triplestar 2 Cam. Angular separations, absolute position angles and relativephotometry result from these observations. The angular separation isderived from the power spectrum. The position angle and the relativephotometry are determined by two recent techniques: thecross-correlation between the speckle images and their square, and theratios of twofold probability density functions of the images. Based onobservations made at 2m Telescope Bernard Lyot, Pic du Midi, France.
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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.
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Map-based trigonometric parallaxes of open clusters - The Pleiades
The multichannel astrometric photometer and Thaw refractor of theUniversity of Pittsburgh's Allegheny Observatory have been used todetermine the trigonometric parallax of the Pleiades star cluster. Thedistance determined, 150 with a standard error of 18 parsecs, places thecluster slightly farther away than generally accepted. This suggeststhat the basis of many estimations of the cosmic distance scale isapproximately 20 percent short. The accuracy of the determination islimited by the number and choice of reference stars. With carefulattention to the selection of reference stars in several Pleiadesregions, it should be possible to examine differences in the photometricand trigonometric modulus at a precision of 0.1 magnitudes.
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Spectroscopic parallaxes of MAP region stars from UBVRI, DDO, and uvbyH-beta photometry
This paper presents the results of spectral type and luminosityclassification of reference stars in the Allegheny Observatory MAPparallax program, using broadband and intermediate-band photometry. Inaddition to the use of UBVRI and DDO photometric systems, the uvbyH-betaphotometric system was included for classification of blue (B - V lessthan 0.6) reference stars. The stellar classifications made from thephotometry are used to determine spectroscopic parallaxes. Thespectroscopic parallaxes are used in turn to adjust the relativeparallaxes measured with the MAP to absolute parallaxes. A new methodfor dereddening stars using more than one photometric system ispresented. In the process of dereddening, visual extinctions, spectraltypes, and luminosity classes are determined, as well as a measure ofthe goodness of fit. The measure of goodness of fit quantifiesconfidence in the stellar classifications. It is found that the spectraltypes are reliable to within 2.5 spectral subclasses.
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Determination of the Proper Motions for Stars in the Region of the Pleiades - Part One
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Interstellar extinction in the direction of the Merope dark cloud in Pleiades
The dependence of interstellar extinction on distance in the directionof the dark cloud south of Merope is determined using photoelectricphotometry of 93 stars in the Vilnius photometric system. The cloudfront edge is detected at 120-130 pc from the sun, and the distance ofthe Pleiades cluster is found to be 127 pc. Mean extinction, A(V), inthe Merope cloud is of the order of 1.0 mag. There is no evidence ofextinction at distances exceeding the Merope cloud distance. Thevariable extinction method yields R = A(V)/E(B-V) = 3.6, while themaximum polarization wavelength method gives the value 3.4. SomePleiades stars are suspected to be unresolved binaries.
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Wide binaries in the Pleiades
The numbers and distributions of wide binary stars in the Pleiades starcluster are compared with those of the solar neighborhood. The numbersof distances between stars in Hertzsprung's (1947) catalog of stars inthe inner region of the Pleiades lying within given intervals werecounted and compared with the expected numbers of optical pairs for arandom distribution of stars in order to obtain the number of visualbinaries. For both a parametric representation of stars in the solarneighborhood and a selection of the nearby binaries with magnitudesgreater than that corresponding to the limit of 16 at the distance ofthe Pleiades, it is found that the magnitude and distance statistics ofthe two regions are in general agreement. The only significant deviationis the deficit of systems with fainter companions in the Pleiadescompared with local stars.
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Comparison of proper motions obtained by means of rectilinear trajectories of optical double stars with those given by the SAO catalog
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979A&A....71...55D&db_key=AST
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Double star measures at Lick Observatory, Mount Hamilton, California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978PASP...90..465H&db_key=AST
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Errata in published observational data
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A spectroscopic investigation of the Pleiades.
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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
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On the inclination of rotation axes in visual binaries.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJ...190..331W&db_key=AST
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On the relationship between the apparent magnitudes given in several catalogues and the UBV system.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&AS...15..215O&db_key=AST
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Observations of occultations of stars by the moon
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&AS...13..395H&db_key=AST
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Accurate positions of 502 stars in the region of the Pleiades
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Mesures d'étoiles doubles visuelles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....3...71M&db_key=AST
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Mikrometermessungen von Doppelsternen. VI.
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Mikrometermessungen von Doppelsternen. V
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Mesures d'étoiles doubles faites au réfracteur de 38 cm de l'Observatoire de Nice
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Mesures d'étoiles doubles faites au 0,38 m de l'Observatoire de Paris.
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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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Polarisation des Sternlichtes im Gebiet der Plejaden. Mit 10 Textabbildungen
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Star in the group of the Pleiades but not belonging to the physical system.
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Photovisual magnitudes of the stars in the Pleiades.
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