The HIPPARCOS proper motion of the Magellanic Clouds
The proper motion of the Large (LMC) and Small (SMC) Magellanic Cloudusing data acquired with the Hipparcos satellite is presented. Hipparcosmeasured 36 stars in the LMC and 11 stars in the SMC. A correctlyweighted mean of the data yields the presently available most accuratevalues, mu_alpha cos(delta) = 1.94 +/- 0.29 mas/yr, mu_delta = - 0.14+/- 0.36 mas/yr for the LMC. For the SMC, mu_alpha cos(delta) = 1.23 +/-0.84 mas/yr, mu_delta = - 1.21 +/- 0.75 mas/yr is obtained, whereby careis taken to exclude likely tidal motions induced by the LMC. Bothgalaxies are moving approximately parallel to each other on the sky,with the Magellanic Stream trailing behind. The Hipparcos proper motionsare in agreement with previous measurements using PPM catalogue data byKroupa et al. (1994), and by Jones et al. (1994) using backgroundgalaxies in a far-outlying field of the LMC. For the LMC the Hipparcosdata suggest a weak rotation signal in a clockwise direction on the sky.Comparison of the Hipparcos proper motion with the proper motion of thefield used by Jones et al. (1994), which is about 7.3 kpc distant fromthe center of the LMC, also suggests clockwise rotation. Combining thethree independent measurements of the proper motion of the LMC and thetwo independent measurements of the proper motion of the SMC improvesthe estimate of the proper motion of the LMC and SMC. The correspondinggalactocentric space motion vectors are computed. Within theuncertainties, the LMC and SMC are found to be on parallel trajectories.Recent theoretical work concerning the origin of the Magellanic Systemis briefly reviewed, but a unique model of the Magellanic Stream, forthe origin of the Magellanic Clouds, and for the mass distribution inthe Galaxy cannot yet be decided upon. Future astrometric space missionsare necessary to significantly improve our present knowledge of thespace motion of the two most conspicuous galactic neighbours of theMilky Way.
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Luminosities of yellow supergiants from near-infrared spectra - Calibration through Magellanic Cloud stars
The possibility of using medium resolution spectrograms in the nearinfrared region to determine luminosities of A-G supergiants has beenexplored. A sample of 49 of these stars has been observed in the twoMagellanic Clouds, and using the intensities of the O I 7774 triplet andan index (CP), which is a combination of the Ca II triplet and Paschenlines intensities, a preliminary luminosity calibration, based on LMCstars, has been obtained. Such a calibration predicts reliableluminosities for Galactic supergiants, and offers the advantage of beingcompletely reddening independent. The reddening free CP index combinedwith BVRI color indices has also been used to estimate the interstellarreddenings of Magellanic Cloud stars.
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Positional reference stars in the Magellanic Clouds
The equatorial coordinates are determined of 926 stars (mainly ofgalactic origin) in the direction of the Magellanic Clouds at the meanepoch T = 1978.4 with an overall accuracy characterized by the meanvalues of the O-C coordinates, Sa = 0.35 arcsec and Sd = 0.38 arcsec,calculated from the coordinates of the Perth reference stars. Thesevalues are larger than the accuracy expected for primary standard stars.They allow the new positions to be considered as those of reliablesecondary standard stars. The published positions correspond to anunquestionable improvement of the quality of the coordinates provided inthe current catalogs. This study represents an 'astrometric step' in thestarting of a 'Durchmusterung' of the Magellanic Clouds organized by deBoer (1988, 1989).
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Astrometry of SN 1987A and SK -69.202 deg
Two sets of astrometric plates (epochs 1987.2 and 1973.0) and asecondary reference system comprised of LMC members were used todetermine the position of SN 1987A relative to about 30 Perth 70 stars.The positional coincidence of the SN and Star 1 of Sanduleak -69 deg 202is confirmed to within an uncertainty of + or - 0.13 arcsec in eachcoordinate. The relative brightness of the two major components of Sk-69 deg 202 was assessed by fitting the density profiles of the blendedimages.
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Photometric Studies of Magellanic Cloud Supergiants. II. Variability
Abstract image available at:http://adsabs.harvard.edu/abs/1986ApJS...62..451G
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Photometric studies of Magellanic Cloud supergiants. I - Mean magnitudes and reddenings. II - Variability
In the first part of this paper, a combination of spectral types for 81LMC and 46 SMC supergiants from the literature with new BVRI photometryyields reddenings and intrinsic colors for these stars. While reddeningsup to E(B-V) of 0.3 are found for the LMC sample, the figure for the SMCappears to be no more than 0.2. The dust/gas ratio in both galaxies isfound to be lower than in the Milky Way. In the second part, individualBVRI photoelectric observations for 88 LMC and 46 SMC intermediatespectral type supergiants are analyzed for variability. It is noted that45 percent of the stars exhibit significant variations, with theincidence of variability decreasing with decreasing luminosity.
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Radial velocities from objective-prism plates in the direction of the Large Magellanic Cloud
A catalog is presented of 711 Large Magellanic Cloud (LMC) stars, withattention to the radial velocities of 418 of these. Also given are theradial velocities of 1127 galactic stars in the direction of the LMC, aswell as discussions of the precision of these measurements and of radialvelocity dispersion in different fields.
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A catalogue of A- and F-type supergiants in the Large Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24...35S&db_key=AST
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UBV photometry for supergiants of the Large Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975A&A....43..345B&db_key=AST
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Radial velocities from objective-prism plates in the direction of the Large Magellanic Cloud. List of 398 stars, LMC members. List of 1434 galactic stars, in the LMC direction
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&AS...13..173F&db_key=AST
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Rotation et masse DU grand nuage de Magellan.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....28..165P&db_key=AST
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Spectrographic and photometric observations of supergiants and foreground stars in the direction of the Large Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&AS....6..249A&db_key=AST
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BVRI-Photometry of the Brightest Stars in the Magellanic Clouds
We have made photometric observations in the BVRI system of 100 objectsthat belong to the Magellanic Clouds. The observational data indicate atleast two remarkable differences between some of the Magellanic Cloudobjects and the supergiant stars in the Galaxy, namely, the former aremore luminous than the most luminous galactic supergiants and they alsohave a color excess in V-R unexplained by interstellar extinction alone.Two possible explanations are likely for the additional color excess;either the presence of a circumstellar dust envelope or a differentchemical atmospheric composition from galactic supergiant stars, orperhaps both of them.
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Five-colour photometry of supergiants and the dust-to-gas ratio in the Large Magellanic Cloud.
Abstract image available at:http://adsabs.harvard.edu/abs/1970A&A.....7...49V
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A deep objective-prism survey for Large Magellanic Cloud members
Not Available
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Grand Nuage de Magellan. Liste des etoiles membres DU Grand Nuage de Magellan et liste d'etoiles galactiques
Not Available
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A Method for Determining Magellanic Membership using an Objective Prism and an Absorption Filter [errata: 1970MNSSA..29....1W, 1970MNSSA..29...13F]
Not Available
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Equivalent widths of Hγ in stellar spectra of the Magellanic Clouds
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.132..433H&db_key=AST
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Mesures de vitesses radiales dans la direction du Grand Nuage de Magellan
Not Available
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Vitesses radiales dans la direction du Grand Nuage de Magellan
Not Available
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A study of the 30 Doradus region of the Large Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/abs/1961MNRAS.122....1F
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The brightest stars in the Magellanic Clouds
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.121..337F&db_key=AST
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Catalogues of Hα-EMISSION Stars and Nebulae in the Magellanic Clouds.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJS....2..315H&db_key=AST
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