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High resolution spectroscopy over lambda lambda 8500-8750 Å for GAIA. IV. Extending the cool MK stars sample
A library of high resolution spectra of MK standard and reference stars,observed in support to the GAIA mission, is presented. The aim of thispaper is to integrate the MK mapping of Paper I of this series as wellas to consider stars over a wider range of metallicities. Radialvelocities are measured for all the target stars.The spectra are available in electronic form (ASCII format) at CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/406/995 and from the webpage http://ulisse.pd.astro.it/MoreMK/, where further bibliographicalinformation for the target stars is given.
| Evolution of the Fu Orionis Object BBW 76
We have carried out a long-term photometric and spectroscopic monitoringprogram of the southern FU Orionis-type object BBW 76 spanning theperiod from 1982 to 1997. BBW 76 has the same radial velocity as thesmall cloud toward which it is projected, and for which a kinematicdistance of about 1.8 kpc has been derived. We have determined a largereddening of E(B-V)~0.7 for BBW 76. Optical and infrared spectra showthe change toward later spectral type with increasing wavelengthcharacteristic of FU Orionis stars and indicative of a hot luminousdisk. High-resolution echelle spectra of BBW 76 show P Cygni profileswith extended blueshifted absorption troughs at the Hα and sodiumlines from a neutral, supersonic wind. Comparison of such spectraobtained at six different epochs between 1985 and 1997 reveals majorchanges in these Hα and sodium line profiles. For a period of 10years from 1985, the massive absorption troughs diminished in extent anddepth, until by 1994 they had all but disappeared, while at the sametime the blueshifted emission peak in the Hα line increasedmarkedly in strength. However, when observed in 1997, the absorption hadincreased again and the emission had diminished. We interpret this interms of an extended period during which accretion through acircumstellar disk decreased, with a resulting decrease in windproduction. But the increased activity by 1997 shows that this is not aconstant decay and that the star was not about to revert to itspresumably original T Tauri stage. We monitored the star with opticalphotometry from 1983 to 1994, during which period it decreased almostmonotonically in brightness by 0.2 mag in V. Infrared J, H, and Kphotometry from 1983 to 1991 shows a period of monotonic fading between1984 and 1988, followed by more irregular behavior. In a search of theHarvard plate archives we have found a plate from the year 1900 on whichBBW 76 is seen at approximately its present brightness, certainly not 2mag brighter as expected if the optical decline between 1983 and 1994had persisted during the whole century. Also, a plate taken for theFranklin-Adams charts in 1927 again shows BBW 76 at approximately thesame brightness. This historical light curve makes BBW 76 the FU Orionisstar with the longest-documented period in a high state. Overall, theobservations suggest that BBW 76 is virtually identical to the prototypeof its class, FU Orionis itself, in all respects except that BBW 76 hasnot shown the regular fading that FU Orionis has displayed after itseruption in 1936. This may be due to continued replenishment of thecircumstellar accretion disk.
| A catalog of rotational and radial velocities for evolved stars. II. Ib supergiant stars
Rotational velocity vsin i and mean radial velocity are presented for asample of 231 Ib supergiant stars covering the spectral region F, G andK. This work is the second part of the large survey carried out with theCORAVEL spectrometer to establish the behavior of the rotation for starsevolving off the main sequence (De Medeiros & Mayor 1999). Thesedata will add constraints to the study of the rotational behavior inevolved stars, as well as solid information concerning tidalinteractions in binary systems and on the link between rotation,chemical abundance and activity in stars of intermediate masses. Basedon observations collected at the Haute-Provence Observatory,Saint-Michel, France and at the European Southern Observatory, La Silla,Chile Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/395/97
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| The Normal Energy Distributions in Stellar Spectra: Giants and Supergiants
We have derived the normal spectral energy distributions for thoseearly-type subgiants, giants, and supergiants that were not investigatedin our earlier studies, which were in most cases also not included inthe studies of Sviderskiene. Color indices computed using our normalenergy distributions are in good agreement with normal colors derivedfrom observations in the Vilnius photometric system. The reliability ofour distribution curves is also demonstrated by comparisons of observedand computed (W-B)-(B-V) two-color diagrams in the WBVR system. Normalcolor indices for the photometric WBVR system are derived.
| Ca II activity and rotation in F-K evolved stars
Ca II H and K high resolution observations for 60 evolved stars in thefield and in 5 open clusters are presented. From these spectrachromospheric fluxes are derived, and a homogeneous sample of more than100 giants is built adding data from the literature. In addition, formost stars, rotational velocities were derived from CORAVELobservations. By comparing chromospheric emission in the cluster starswe confirm the results of Pasquini & Brocato (1992): chromosphericactivity depends on the stellar effective temperature, and mass, whenintermediate mass stars (M ~ 4 Msun) are considered. TheHyades and the Praesepe clump giants show the same level of activity, asexpected from stars with similar masses and effective temperatures. Adifference of up to 0.4 dex in the chromospheric fluxes among the Hyadesgiants is recorded and this sets a clear limit to the intrinsic spreadof stellar activity in evolved giants. These differences in otherwisevery similar stars are likely due to stellar cycles and/or differencesin the stellar initial angular momentum. Among the field stars none ofthe giants with (V-R)o < 0.4 and Ia supergiants observedshows a signature of Ca II activity; this can be due either to the realabsence of a chromosphere, but also to other causes which preclude theappearance of Ca II reversal. By analyzing the whole sample we find thatchromospheric activity scales linearly with stellar rotational velocityand a high power of stellar effective temperature: F'k ~Teff7.7 (Vsini)0.9. This result can beinterpreted as the effect of two chromospheric components of differentnature: one mechanical and one magnetic. Alternatively, by using theHipparcos parallaxes and evolutionary tracks, we divide the sampleaccording to the stellar masses, and we follow the objects along anevolutionary track. For each range of masses activity can simply beexpressed as a function of only one parameter: either theTeff or the angular rotation Omega , with laws F'k~ Omega alpha , because angular velocity decreases witheffective temperature along an evolutionary track. By using theevolutionary tracks and the observed Vsini we investigate the evolutionof the angular momentum for evolved stars in the range 1-5Msun. For the 1.6-3 solar mass stars the data are consistentwith the IOmega =const law while lower and higher masses follow a lawsimilar to IOmega 2=const, where I is the computed stellarmomentum of inertia. We find it intriguing that Vsini remains almostconstant for 1Msun stars along their evolution; if a similarbehavior is shared by Pop II stars, this could explain the relativelyhigh degree of activity observed in Pop II giants. Finally, through theuse of models, we have verified the consistency of the F'k ~Omega alpha and the IOmega beta = Const lawsderived, finding an excellent agreement. This representation, albeitcrude (the models do not consider, for instance, mass losses) representsthe evolution of Ca II activity and of the angular momentum in asatisfactory way in most of the portion of HR diagram analyzed.Different predictions could be tested with observations in selectedclusters. Based on observations collected at ESO, La Silla. Tables 1-3are only available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Red supergiants in the LMC - III: luminous F and G stars
New BVRI observations for 40 and spectrophotometric measurements for 23F to G LMC supergiant candidates (and 3 galactic F to G supergiants) arepresented. The errors of the BVRI data are 0.01 to 0.03 mag in mostcases. The wavelength range of the spectra is 3400 to 6400 Angstroms,their resolution 10 Angstroms. The mean error of the fluxes is 0.03 mag.Spectral indices measuring the strengths of the Hβ , Hγ ,Hdelta , NaD and CaII H+K lines, the CHα_ {0} and CNbeta_ {0}bands, of the Balmer jump and the slope of the continuum redwards arediscussed as measures of effective temperature and luminosity on thebasis of galactic stars with accurate MK types and parallaxes. TheHγ line and the continuum gradient are very good temperaturecriteria, the CHα_ {0} band and especially the Balmer jump forluminosity. The luminosity classification given for F to G supergiantcandidates in the LMC in the literature is often doubtful. 5 of the 23stars observed spectrophotometrically turn out to be probably galacticforeground dwarfs on the basis both of the Balmer jump and thecomparison of their flux distributions with synthetic ones based on theKurucz model atmospheres. Surface gravities derived purely on the basisof flux distributions and such ones given by models of stellar evolutionagree with each other for dwarfs and giants only. For supergiants theformer are about 1.0 dex higher than the latter. As a consequenceeffective temperatures and metallicities given by these two methodsdeviate from each other for such stars, too. The intrinsic colours andtemperatures of galactic and LMC supergiants do not differ. Withabsolute magnitudes up to -9.6 mag the upper luminosity limit in the LMCdoes not exceed that in the Galaxy, where Ia-0 supergiants haveMV of up to -9.5 mag. The metallicities of the supergiantsshow a rather large scatter. Nevertheless the mean metallicities of 0.02+/- 0.09 dex for the Galaxy and -0.26 +/- 0.10 dex for the LMC agreewell with other observations.
| BA II lines as luminosity indicators: s-Cepheids and non-variable supergiants
Ba II line equivalent widths appear to be well correlated with theabsolute magnitudes for yellow supergiants. Two Ba II lines 5853.6Angstroms and 6141.7 Angstroms were applied for investigation of thepossible relation between their equivalent widths and Mv forsmall-amplitude Cepheids and non-variable supergiants.
| Spectral energy distributions and physical parameters of the atmospheres of main-sequence A stars with infrared excesses: Comparison with normal stars
For eight stars with infrared excesses greater than 0.5m in the IRASbands, we obtained the energy distribution over the range 3200-7600Angstroms and measured their infrared JHKLM magnitudes. Similarobservations were performed for 21 stars of various subclasses of thespectral type A with excesses no greater than 0.3m. Based on the energydistribution derived from the response curves of the photometric UBV andWBVR systems, we computed the synthetic B-V color indices, which are ingood agreement with the photometric observations. A comparison of thenormalized energy distribution in the spectra of A stars with infraredexcesses greater than 0.5m in the IRAS bands and the mean energydistribution for stars of the corresponding subclasses shows that themaximum difference does not exceed 10% both in the ultraviolet(3200-4000 Angstroms) and in the near infrared (up to 7600 Angstroms) Inall of the stars studied, we detected no excesses in the JHKLM bandsthat were greater than the accuracy of our measurements. Using themethod of infrared fluxes and comparing the observed energy distributionwith theoretical models of Kurucz, we determined the effectivetemperatures and angular diameters of the stars. For three stars, weestimated the parameters of their dust shells.
| CA II K Emission Line Asymmetries Among Red Giants
In the spectra of red giants the chromospheric emission feature found inthe core of the Ca II K line often exhibits an asymmetric profile. Thisasymmetry can be documented by a parameter V/R which is classified as> 1, 1, or < 1 if the violet wing of the emission profile is ofgreater, equal, or lower intensity than the redward wing. A literaturesearch has been conducted to compile a V/R dataset which builds on thelarge survey of bright field giants made by Wilson (1976). Among starsof luminosity classes II-III-IV the majority of those with V/R > 1are found to be bluer than B-V =1.3, while those with V/R < 1 aremostly redder than this colour. Stars with nearly symmetric profiles,V/R≈ 1, are found throughout the colour range 0.8 < B-V < 1.5.There is no sharp transition line separating stars of V/R > 1 and< 1 in the colour-magnitude diagram, but rather a `transition zone'centered at B-V ≈ 1.3. The center of this zone coincides closely witha `coronal dividing line' identified by Haish, Schmitt and Rosso (1991)as the red envelope in the H-R diagram of giants detected in soft x-rayemission by ROSAT. It is suggested that both the transition to a Ca II Kemission asymmetry of V/R < 1 and the drop in soft x-ray activityacross the coronal dividing line are related to changes in the dynamicalstate of the chromospheres of red giants. By contrast, the onset ofphotometric variability due to pulsation occurs among stars of early-Mspectral type, that are redward of the mid-point of the Ca II V/R`transition zone', suggesting that the chromospheric motions whichproduce an asymmetry of V/R < 1 are established prior to the onset ofpulsation.
| Quantitative spectral classification based on photoelectric spectrum scanner measurements of F-K stars.
New criteria of quantitative spectral classification have beenintroduced and the method of stepwise linear regression to thesecriteria for quantitative spectral classification of F-K stars has beenapplied to the Bochum photoelectric spectra.
| DDO photometry of E-region stars and equatorial standards - II
This paper deals with the observations of 72 of McClure's equatorialstandard stars, made with the same photometer and DDO filters as wereused for the E-region stars in Cousins' Paper I in order to standardizethe observations. These observations were reduced in the natural systemand later transformed into McClure's system. Zero-point ties between theequatorial and E-region stars were also needed to standardize the lattersystem. With the exception of C(38-41), our photometry agrees as wellwith McClure's standard system as his own observations do, but both showsome small, apparently systematic, differences which are almostinevitable with a system like the DDO unless the response functions arevery well matched. Comparisons with 17 of Dean's measurements ofE-region stars show good agreement (~2 mmag) for the averagedzero-points, but there are small colour differences affecting C(35-38)and C(38-41) because of differences between the filters and thereduction procedures. This paper also deals with several problems in theDDO photometry that have implications for precision photometry ingeneral.
| The Comparable Analysis of the Cepheids and Non-Variable Supergiants from the Instability STRIP.I.
Not Available
| The photoelectric astrolabe catalogue of Yunnan Observatory (YPAC).
The positions of 53 FK5, 70 FK5 Extension and 486 GC stars are given forthe equator and equinox J2000.0 and for the mean observation epoch ofeach star. They are determined with the photoelectric astrolabe ofYunnan Observatory. The internal mean errors in right ascension anddeclination are +/- 0.046" and +/- 0.059", respectively. The meanobservation epoch is 1989.51.
| A uvbyβ photometric calibration of iron abundances in supergiant stars.
A photometric reddening-free calibration for [Fe/H] valid for giant andsupergiant stars of intermediate temperature, has been obtained usingthe Stroemgren uvbyβ system. Galactic supergiants, supergiants inthe Magellanic Clouds and Galactic metal deficient red giants withspectroscopic determinations of [Fe/H] were used as calibrators. Thecalibration can be used to predict [Fe/H] with an accuracy of 0.33 dex,valid for stars with 0.14<[m_1_]<0.70 in the iron abundance range-2.5<[Fe/H]<+0.3. This shows the potential of supergiant stars astracers of iron abundances in other galaxies. Evidence that Galacticluminous F-G stars are intrinsically bluer than their counterparts inthe Magellanic Clouds is offered.
| 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.
| Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.
| Spectral classifications in the near infrared of stars with composite spectra. I. The study of MK standards.
Up to now the spectral classifications of the cool components ofcomposite spectra obtained in the 3800-4800A wavelength region have beenvery disparate. These disparities are due to the fact that the spectraof the evolved cool component are strongly veiled by that of the hotterdwarf component, which makes a classification very difficult. We proposeto study these systems in the near infrared (8380-8780A). In thisspectral domain the magnitude difference between the spectra of thecomponents is in general sufficiently large so that one observespractically only the spectrum of the cool component. In this first paperwe provide, for a sample of MK standards, the relations between theequivalent width (Wlambda_ ) of certain lines and thespectral classifications. For the cool G, K and M type stars, the linesconsidered are those of the calcium triplet (Ca II 8498, 8542 and 8662),of iron (Fe I 8621 and 8688), of titanium (Ti I 8426 and 8435) and ofthe blend λ8468. The use of certain line intensity ratiospermits, after eliminating partially the luminosity effects, a firstapproach to the spectral type. For the hotter stars of types O, B, A andF we study the behavior of the hydrogen lines (P12 and P14), the calciumlines (Ca II 8498 and 8542) as well as those of the oxygen (O I 8446).The latter line presents a very characteristic profile for stars of lowrotation and therefore in Am stars, which are frequently found among thecomposite spectrum binaries. Among the cooler stars of our sample, only6% present real anomalies with respect to the MK classifications. Thisresult is very encouraging for undertaking the classification of asample of composite spectra. The spectra were taken at the Observatoirede Haute-Provence (OHP) with the CARELEC spectrograph at the 193 cmtelescope, with a dispersion of 33 A/mm.
| NGC 2024-IRS2: an outburst in its near-infrared line and continuum emission
We present new near infrared spectroscopy, photometry, and narrow bandimaging of the young stellar object NGC 2024-IRS2. The data include highand low resolution spectra of Brγ, Brα, and Pfγ,single channel, JHKL' photometry, and images in Brγ and nearbycontinuum. The source has had a burst in its infrared emission,typically increasing by one magnitude in continuum brightness and byfactors of 4-8 in line intensity, since 1989, and apparently reached amaximum in 1991. A large velocity shift has occurred in the peaks of thehydrogen lines, from ~+40km/s LSR in 1984 to ~-25km/s at present.Observation of such dramatic changes is unprecedented in studies ofluminous YSO's. The data exclude external phenomena such as variableextinction or binary occultation as the origin of the observedvariability, and appear more indicative of changes in the physicalconditions of the star and its circumstellar environment.
| The southern Vilnius photometric system. I - Transformation to the standard system
This paper is the first in a series on the extension of the Vilniusphotometric system to the southern hemisphere. Observations of a commonset of 73 stars measured in both hemispheres are described and ananalysis of the differences is given.
| Calibrations of Mv, (Fe/H), and log G for yellow supergiant stars from O I 7774 and uvby-beta data
New calibrations of the absolute magnitude Mv from O I 7774data are derived from narrow-band photometry and low dispersionspectroscopy for AO-G2 low and high luminosity stars. The nonlineardependence of Mv from the equivalent width W(OI) and therelevance of the stellar temperature in the calibration are confirmed inagreement with previous calibrations obtained from high resolutionspectroscopy. Also functional formulas to estimate (Fe/H) and log g fromuvby-beta data for FO-G3 supergiants are offered. These calibrationspredict iron abundances and gravities for yellow supergiants withuncertainties not much higher than good spectroscopic determinations.
| Photometry of F-K type bright giants and supergiants. I - Intermediate band and H-Beta observations
Over 1500 observations of 560 bright giants and supergiants of types F-Kare presented and compared to the observations by Gray and Olsen (1991).The present results include intermediate-band which is slightlydifferent from the Stromgren data by Gray and Olsen due to a differentwidth for the v filter. A systematic difference in m(1) - M(1) withdecreasing temperature is noted in the two H-Beta data sets, and thecorrelations are defined.
| Chromospheric activity and stellar evolution - Clues from IUE data
We investigate the dependence of chromospheric activity on stellarphysical parameters in a sample of cool giants and supergiants. Ca IIsurface fluxes for stars of known masses and evolutionary status arederived from published IUE Mg II observations. Adding these data to thesample of Pasquini et al. (1990) we find that chromospheric activity inevolved stars is better described by two stellar parameters, and a tightrelationship is found between activity, stellar Teff and Mass. Wediscuss this relationship arguing that the stellar evolutionary statuscould play a 'hidden' but fundamental role in determining the activitylevel of evolved late type stars.
| A photometric study of the G0-4 Ia(+) hypergiant HD 96918 (V382 Carinae)
Using a photometric method we derive T(eff), log g, and E(B-V) for thestar HD 96918 and also for 35 supergiants of similar spectral class. ForHD 96918 we found T(eff) = 5200 +/- 200 K and log g (cm/sq s) = 0.0 +/-0.5. The comparison of the results indicates that HD 96918 is really ahypergiant with a spectral class around G0-G4. We also estimate thedistance of HD 96918 using the kinematic and reddening methods, and bycomparing its T(eff) and log g with evolutionary calculation. Weconsistently find a distance of 2.7 +/- 1.0 kpc which implies logL/solar luminosity = 5.5 +/- 0.4. A most probable mass for the star is20 +/- 10 solar mass.
| CA II H and K measurements made at Mount Wilson Observatory, 1966-1983
Summaries are presented of the photoelectric measurements of stellar CaII H and K line intensity made at Mount Wilson Observatory during theyears 1966-1983. These results are derived from 65,263 individualobservations of 1296 stars. For each star, for each observing season,the maximum, minimum, mean, and variation of the instrumental H and Kindex 'S' are given, as well as a measurement of the accuracy ofobservation. A total of 3110 seasonal summaries are reported. Factorswhich affect the ability to detect stellar activity variations andaccurately measure their amplitudes, such as the accuracy of the H and Kmeasurements and scattered light contamination, are discussed. Relationsare given which facilitate intercomparison of 'S' values with residualintensities derived from ordinary spectrophotometry, and for convertingmeasurements to absolute fluxes.
| An uvby-beta catalogue of F0-K0 supergiant stars brighter than V = 6.5
Photoelectric uvby-beta photometry is reported for 111 F0-K0 supergiantstars which are brighter than V = 6.5 mag and located betweendeclination of -15 and +61 deg. A comparison with previous observationsis made. A few stars which are suspected to present light variations arementioned.
| Mass-losing M supergiants in the solar neighborhood
A list of the 21 mass-losing red supergiants (20 M type, one G type; Lgreater than 100,000 solar luminosities) within 2.5 kpc of the sun iscompiled. These supergiants are highly evolved descendants ofmain-sequence stars with initial masses larger than 20 solar masses. Thesurface density is between about 1 and 2/sq kpc. As found previously,these stars are much less concentrated toward the Galactic center thanW-R stars, which are also highly evolved massive stars. Although withconsiderable uncertainty, it is estimated that the mass return by the Msupergiants is somewhere between 0.00001 and 0.00003 solar mass/sq kpcyr. In the hemisphere facing the Galactic center there is much less massloss from M supergiants than from W-R stars, but, in the anticenterdirection, the M supergiants return more mass than do the W-R stars. Theduration of the M supergiant phase appears to be between 200,000 and400,000 yr. During this phase, a star of initially at least 20 solarmasses returns perhaps 3-10 solar masses into the interstellar medium.
| IUE and Einstein survey of late-type giant and supergiant stars and the dividing line
Results are presented on an IUE UV survey of 255 late-type G, K, and Mstars, complementing the Maggio et al. (1990) Einstein X-ray survey of380 late-type stars. The large data sample of X-ray and UV detectionsmake it possible to examine the activity relationship between the X-rayand the UV emissions. The results confirm previous finding of a trendinvolving a steeply-dropping upper envelope of the transition regionline fluxes, f(line)/f(V), as the dividing line is approached. Thissuggests that a sharp decrease in maximum activity accompanies theadvancing spectral type, with the dividing line corresponding to thissteep gradient region. The results confirm the rotation-activityconnection for stars in this region of the H-R diagram.
| Colour excesses and absolute magnitudes for non-Cepheid F-G supergiants from uvbybeta photometry
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&A...239..205A&db_key=AST
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Pozíciós és asztrometriai adatok
| Csillagkép: | Egyszarvú |
| Rektaszcenzió: | 08h08m35.60s |
| Deklináció: | -02°59'02.0" |
| Vizuális fényesség: | 4.34 |
| Távolság: | 568.182 parszek |
| RA sajátmozgás: | -15.4 |
| Dec sajátmozgás: | -3.5 |
| B-T magnitude: | 5.57 |
| V-T magnitude: | 4.456 |
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