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Asteroseismology of the β Cephei star 12 (DD) Lacertae: photometric observations, pulsational frequency analysis and mode identification
We report a multisite photometric campaign for the β Cephei star 12Lacertae. 750 h of high-quality differential photoelectricStrömgren, Johnson and Geneva time-series photometry were obtainedwith nine telescopes during 190 nights. Our frequency analysis resultsin the detection of 23 sinusoidal signals in the light curves. Ten ofthose correspond to independent pulsation modes, and the remainder arecombination frequencies. We find some slow aperiodic variability such asthat seemingly present in several β Cephei stars. We perform modeidentification from our colour photometry, derive the spherical degree lfor the five strongest modes unambiguously and provide constraints on lfor the weaker modes. We find a mixture of modes of 0 <=l<= 4. Inparticular, we prove that the previously suspected rotationally splittriplet within the modes of 12 Lac consists of modes of different ltheir equal frequency splitting must thus be accidental.One of the periodic signals we detected in the light curves is argued tobe a linearly stable mode excited to visible amplitude by non-linearmode coupling via a 2:1 resonance. We also find a low-frequency signalin the light variations whose physical nature is unclear; it could be aparent or daughter mode resonantly coupled. The remaining combinationfrequencies are consistent with simple light-curve distortions.The range of excited pulsation frequencies of 12 Lac may be sufficientlylarge that it cannot be reproduced by standard models. We suspect thatthe star has a larger metal abundance in the pulsational driving zone, ahypothesis also capable of explaining the presence of β Cepheistars in the Large Magellanic Cloud.

Application of time-dependent convection models to the photometric mode identification in delta Scuti stars
We apply the Time-Dependent Convection (TDC) treatment of Gabriel\cite{Gabriel1996} and Grigahcène \cite{Grigahcene} to the modeidentification and seismic study of delta Sct stars. We compare thenon-adiabatic phase-lags obtained with TDC and Frozen Convection (FC)treatments and show that they are very different at the red side of theinstability strip. Finally, we compare the phase differences betweenlight and velocity curves observed for the star 1 Mon with thetheoretical predictions of TDC and FC models. The much better agreementfound with the TDC models enables us to identify the modes of this starwith a higher degree of confidency.

Time-dependent convection seismic study of δ Sct stars
We apply for the first time the time-dependent convection (TDC)treatment of Gabriel and Grigahcène et al. to the modeidentification and seismic study of δ Sct stars. We consider theinfluence of this treatment on the photometric amplitude ratios andphase differences, and compare our TDC results to frozen convection (FC)results. We also compare the results obtained with different values ofthe mixing-length (ML) parameter α. Finally, we identify the modesand perform a seismic study of the stars V784 Cassiopeae (Cas), 1Monocerotis (Mon) and 28 Andromedae (And), and show that our TDC modelsagree better with observations than FC models.

Asteroseismology of δ Scuti Stars: Problems and Prospects
We briefly outline the state-of-the-art seismology of δ Scutistars from a theoretical point of view: why is it so difficult a task?The recent theoretical advances in the field that these difficultieshave influenced are also discussed.

UBVRIJH photometry of two new luminous δ Scuti stars and the discovery of δ Scuti pulsation in the most evolved Ap star known
Time-series photometry of the Hipparcos variable stars HD 199434 and21190 is reported. Both stars are pulsators of the δ Scuti type.Reclassifications of the MK types of the stars, based on newspectrograms, are given. HD 21190 is found to be F2III SrEuSi:, makingit the most evolved Ap star known. Its Strömgren photometricindices support the peculiar spectral type. It is also one of the mostevolved δ Scuti stars known. Its combined Ap-δ Scuti naturemakes it an important test of models of pulsation in peculiar starsrecently developed by Turcotte et al., although it is more extreme thanany model they examined. Physical parameters of both stars are estimatedfrom Strömgren and Hβ photometry, and Hipparcos absolutemagnitudes. We attempt mode identifications based on amplitude ratiosand phase differences from our photometry. The dominant pulsation of HD21190 may be an overtone radial mode. The model fits for HD 199434 areeven less satisfactory, but favour an l=2 mode. Given the good qualityand wavelength coverage of our data, the poor results from theapplication of the photometric theory of mode identification may callinto question the use of that technique.

Mode identification in the δ Scuti Star 1 Mon
We present new multicolour photometry and simultaneous high-dispersionspectroscopy for the δ Scuti star 1 Mon. The two mainperiodicities in the star are still present, but the third known periodis not directly detected in the new radial velocities or lightvariations. However, it is detected in the periodogram of the secondmoment of the line profile variations. We use the cross-correlationfunction as an approximation for the line profile variations. Bycomputing theoretical profiles for a given mode and comparing them withphased cross-correlation profiles, we are able to determine agoodness-of-fit criterion and estimate the most probable sphericalharmonic degree, l, the azimuthal order, m, of the pulsation and alsothe angle of inclination. We then compare the relative amplitudes andphases of the photometric variations in five wavebands and obtain thebest estimates of l for the two visible periodicities. We confirm theearlier determinations that the main periodicity is a radial mode andthat the other periodicity is probably l=1, m=-1. We show that the lineprofile variations and light variations give consistent results. Wepoint out the importance of a long wavelength range when using thephotometric mode identification technique. Finally, we attempt to matchthe two periods with unstable modes from linear, non-adiabaticcalculations. We are able to show that the principal period is wellmatched by either the fundamental or first overtone radial mode, butcould not find a satisfactory fit to the l=1 mode. We discussimplications for mode identification of δ Scuti stars based onwhat we have learned from this star.

Multiperiodicities from the Hipparcos epoch photometry and possible pulsation in early A-type stars
A selection criterion based on the relative strength of the largestpeaks in the amplitude spectra, and an information criterion are used incombination to search for multiperiodicities in Hipparcos epochphotometry. The method is applied to all stars which have beenclassified as variable in the Hipparcos catalogue: periodic, unsolvedand microvariables. Results are assessed critically: although there aremany problems arising from aliasing, there are also a number ofinteresting frequency combinations which deserve further investigation.One such result is the possible occurrence of multiple periods of theorder of a day in a few early A-type stars. The Hipparcos catalogue alsocontains a number of these stars with single periodicities: such starswith no obvious variability classifications are listed, and informationabout their properties (e.g., radial velocity variations) discussed.These stars may constitute a new class of pulsators.

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

On the Variability of F1-F9 Luminosity Class III-V Stars
Hipparcos Satellite photometry of F1-F9 luminosity class III-V starsindicates that most are not particularly variable. A few stars for whichfurther study is desirable are identified.

A revised catalogue of delta Sct stars
An extensive and up-dated list of delta Sct stars is presented here.More than 500 papers, published during the last few years, have beenrevised and 341 new variables have been added to our last list, sixyears ago. This catalogue is intended to be a comprehensive review onthe observational characteristics of all the delta Sct stars known untilnow, including stars contained in earlier catalogues together with othernew discovered variables, covering information published until January2000. In summary, 636 variables, 1149 references and 182 individualnotes are presented in this new list. Tables 1 and 2 will be accessibleonly 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

The delta Scuti Star GSC 2985-01044
GSC 2985-01044 is a delta Scuti star with a period of 0.0933584 days anda V-magnitude range of 11.85-12.05 its light curve is slightly variable.The location, space motion, and other properties of this star indicatethat it is a higher amplitude delta Scuti star (or ``dwarf Cepheid'')that is a member of the old disk population. The problem of determiningthe local space densities of the various populations of the higheramplitude delta Scuti stars is discussed.

HIPPARCOS Parallaxes and Distances of High-Amplitude δ Scuti Stars
Not Available

An extensive Delta a-photometric survey of southern B and A type bright stars
Photoelectric photometry of 803 southern BS objects in the Deltaa-system as detection tool for magnetic chemically peculiar (=CP2) starshas been carried out and compared to published spectral types. Thestatistical yield of such objects detected by both techniques ispractically the same. We show that there are several factors whichcontaminate the search for these stars, but this contamination is onlyof the order of 10% in both techniques. We find a smooth transition fromnormal to peculiar stars. Our sample exhibits the largest fraction ofCP2 stars at their bluest colour interval, i.e. 10% of all stars in thecolour range -0.19 <= B-V < -0.10 or -0.10 <= b-y < -0.05.No peculiar stars based on the Delta a-criterion were found at bluercolours. Towards the red side the fraction of CP2 stars drops to about3% for positive values of B-V or b-y with red limits roughlycorresponding to normal stars of spectral type A5. The photometricbehaviour of other peculiar stars: Am, HgMn, delta Del, lambda Boo, Heabnormal stars, as well as Be/shell stars and supergiants shows someslight, but definite deviations from normal stars. Spectroscopic andvisual binaries are not distinguished from normal stars in their Delta abehaviour. The results of this work justify larger statistical work(e.g. in open clusters) employing more time-saving photometric methods(CCD). \newpage Based on observations obtained at the European SouthernObservatory, La Silla, Chile. This research has made use of the Simbaddatabase, operated at CDS, Strasbourg, France. Table 2 is only availablein electronic form via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html

HIPPARCOS parallaxes and period-luminosity relations of high-amplitude delta Scuti stars
Hipparcos parallaxes of high-amplitude delta Scuti stars are used toderive a period-luminosity relation with a scatter of about +/-0.1 mag,which is independent from photometric calibrations to absoluteluminosities. Comparisons with several P-L relations from the literatureshow satisfactory agreement, and all deviations from the Hipparcos meanrelation can be explained by uncertainties in the data available beforeHipparcos. Hipparcos data for a few stars of relatively small anduncertain parallaxes indicate that they may have systematically very lowluminosity. However, briefly discussing Lutz-Kelker corrections andconsidering the full sample of high-amplitude delta Scuti stars, it isconcluded that this sample is homogeneous and has similar basic physicalproperties as the ``normal'' low-amplitude delta Scuti stars. It isemphasized that the Hipparcos P-L relation defines a new distance scalewhich is independent from those of the classical Cepheids and RR Lyraestars. Therefore, observations of high-amplitude delta Scuti stars canbe used to check fundamental distance determinations to e.g. globularclusters, the Galactic bulge and the Magellanic Clouds.

The absolute magnitude of the early type MK standards from HIPPARCOS parallaxes
We analyse the standards of the MK system with the help of Hipparcosparallaxes, using only stars for which the error of the absolutemagnitude is <= 0.3 mag. We find that the main sequence is a wideband and that, although in general giants and dwarfs have differentabsolute magnitudes, the separation between luminosity classes V and IIIis not clear. Furthermore, there are a number of exceptions to thestrict relation between luminosity class and absolute magnitude. Weanalyse similarly the system of standards defined by Garrison & Gray(1994) separating low and high rotational velocity standards. We findsimilar effects as in the original MK system. We propose a revision ofthe MK standards, to eliminate the most deviant cases. Based on datafrom the ESA Hipparcos astrometry satellite

The HIPPARCOS Mission
Not Available

Amplitude variations of the multimode nonradial δ Scuti pulsator 4 CVn
New photoelectric photometry of the δ Scuti variable 4 CVn revealslong-term slow variations of multimode pulsational frequencies and theiramplitudes. We have confirmed 5(f1, f2,f3, f5, f7) of the 7 frequenciesidentified in the literature. Besides presenting the long-termvariations of the different amplitudes, we have found three newsuspected frequencies in the new data. Although Blazhko effect and moderesonance along with its coupling between different nonradial modesthrough interaction can be reasonably used to explain the observedchanges of periods and amplitudes, it should be carefully checked andanalyzed before RR Lyr-like light curve shape and new pulsation modescan be established with certainty.

Amplitude variations of the multimode nonradial delta Scuti pulsator 4 CVn.
Not Available

Spectroscopic survey of delta Scuti stars. I. Rotation velocities and effective temperatures
Projected rotational velocities and effective temperatures for 68 deltaSct stars as well as 41 non-variable stars of similar spectral type andluminosity are presented here. The rotational velocities have beencalculated following the method developed in \cite[Gray (1992)]{ref38}and effective temperatures have been derived using the Balmer lineprofiles. The temperatures obtained from this method are shown to be inreasonable agreement with those calculated using the Infrared FluxMethod (IRFM) or spectrophotometric methods. This result has allowed usto use our temperatures to compare different uvby beta photometriccalibrations. We find that the calibration given by \cite[Moon \&Dworetsky (1985)]{ref72} is the most consistent. In the second part ofthis paper we have studied the relation between the pulsationalproperties (periods and amplitudes) and the physical parameters (v sin iand Teff). Where pulsation modes have been determined, thelow amplitude $\delta$ Scutis tend to be multimode (radial andnon-radial) pulsators, consistent with the theory that non-linearcoupling between modes acts to limit the amplitude in these stars. Wehave compared the distribution of v sin i for low amplitude $\delta$Scutis and non-variable stars. This shows the $\delta$ Scutis have abroader distribution in v sin i suggesting that a high rotation velocitymay favour pulsation. We find that the large amplitude delta Scuti starstend to have longer periods, cooler temperatures and lower rotationvelocities. Given that the large amplitude stars are also relativelyrare all the above are consistent with the hypothesis that these starsare more evolved (sub-giants) than the low amplitude delta Scutis (mainsequence or early post-main sequence).

Luminosity and related parameters of δ Scuti stars from HIPPARCOS parallaxes. General properties of luminosity.
The absolute magnitudes of δ Scuti stars derived from parallaxesmeasured by the Hipparcos astrometric satellite are discussed andcompared with the previous estimates based on photometric uvbyβindices. There are significant differences which are related tophotometric effects of metallicity and rotational velocity, but thepossible effect of a close companion on the measured apparent magnitudeshould be also taken into account. The possibility of differentgroupings of δ Scuti stars based on the absolute magnitudes isbriefly discussed. Some high amplitude δ Scuti stars withintermediate or normal metallicity and small and uncertain parallax haveapparently a very low luminosity; this could be a systematic effectrelated to the observational errors.

HIPPARCOS parallaxes and the nature of δ Scuti stars.
Hipparcos parallaxes give new tests of the nature of δ Sctvariables. For many individual stars accurate distances are nowavailable, i.e. directly determined luminosities and radii can be usedto test theoretical models. Of particular interest are the at presentvery unclear relations between high-amplitude δ Sct stars and themuch more abundant low-amplitude δ Sct variables, and therelations between field variables and the SX Phe stars in globularclusters. Only a few high-amplitude variables have Hipparcos parallaxessufficiently accurate to provide precise model tests. Here we give adiscussion of this group, considering SX Phoenicis and AI Velorum, whichhave the best parallaxes among the high-amplitude stars, in some detail.It is shown that two new tests based on the improved parallaxes are ingood agreement with the (generally accepted) assumption that thehigh-amplitude variables are normal stars following standard evolution.AD Canis Minoris may be an interesting exception with strongly deviatingproperties. We briefly comment on globular cluster variables andperiod-luminosity relations.

On the role of resonances in nonradial pulsators.
Resonances or near resonances are ubiquitous among the excited nonradialpulsation modes of variable stars and they must play an important rolein determining their pulsational behavior. Here in a first step atnonlinear asteroseismology we explore some of the consequences ofresonances by means of the amplitude equation formalism. We show howparity and angular momentum constraints can be used to eliminate many ofthe possible nonlinear resonant couplings between modes (and multipletsof modes), and how the amplitude equations can thus be simplified. Evenwhen we may not be able, nor wish, to make an ab initio computation ofthe values of the coupling coefficients, it is still possible to obtainconstraints on the nature of the excited modes if a resonance betweenobserved frequencies can be identified. Resonances can cause nonlinearfrequency locking of modes. This means that the observed frequenciesappear in exact resonance even though the linear frequencies are onlyapproximately in resonance. The nonlinear frequency lock, when itoccurs, it does so over a range of departures from linear resonance, andit is accompanied by constant pulsation amplitudes. The locked,nonlinear frequencies can differ noticeably from their nonresonantcounterparts which are usually used in seismology. This is particularlytrue for multiplets of modes split by rotation. Beyond the regime of thefrequency lock, amplitude and frequency modulations can appear in thepulsations. Far from the resonance condition one recovers the regime ofsteady pulsations with nonresonant frequencies for which theseismological studies, as they are presently carried out, are justified(provided furthermore, of course, that nonlinear frequency shifts arenegligible). Success in identifying a resonance in an observed powerspectrum depends on the quality of the data. While keeping thislimitation in mind, we discuss the possible existence of peculiarresonances in the pulsations of specific variable white dwarfs andδ Scuti stars.

γ Doradus and δ Scuti stars: cousins or twins?
γ Doradus stars are a group of slowly pulsating early F dwarfswith typical low frequencies near 1c/d. The pulsation modes are probablyg modes. These stars are slightly cooler than the typical δ Scutivariables, which pulsate with higher frequencies of typically 10c/d(mostly nonradial p modes). This paper examines the relationship betweenthe two groups of variables. Additional low-frequency variability hasbeen reported for fewer than 10% of the 300 δ Scuti starsexamined. In at least one case (1 Mon), the observational data areconsistent with an alternate interpretation in terms of a modeinteraction, f_1_-f_2_, between two p modes of higher frequency, ratherthan by the excitation of g modes. In several other stars (e.g. 4 CVn),the reported low-frequency variability may originate in the comparisonstar used. Arguments are given that for a number of stars the observedlow-frequency variations are caused by observational errors (such asinstrumental drift and transparency variations). A few δ Scutistars remain for which intrinsic γ Doradus-type variability mayalready have been discovered, although no case is well-studied. One ofthe best candidates is the star BI CMi, which is situated in the smallregion of overlap of the two groups of pulsators in theHertzsprung-Russell diagram. The star deserves further study.

Another look at the delta Scuti star FM Comae.
HR Comae (HR 4684) is a low amplitude Delta Scuti type variable. Ananalysis by Papar=DB et al. (1993) of photometric observations obtainedover five years from 1976 to 1989 identified four frequencies, of whichonly one (near 15 cycles day=961) was identified in each year. Weobserved the star on 11 nights in 1992 and four nights in 1993. Aperiodogram analysis of the light curves, divided into four subsets,yielded four frequencies which were present in at least two of thegroups. A significant peak near 15.2 cycles day=961 was present in threeof the groups with an amplitude of about 3 mmag in B; the same frequency(or an adjacent 1 cycle day=961 alias) dominates the Fourier spectrum ofthe entire data set. Although the same frequencies seem to recur, theamplitudes vary with time. A comparison with earlier frequency estimateswould imply period changes over the two decade interval that are manyorders of magnitude too large to be due to stellar evolution. Instead,we argue that different pulsation modes and/or rotationally-split sidelobes have probably been observed at different epochs. The amplitudevariations we observed are consistent with such mode growth and decay.

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.

A catalogue of variable stars in the lower instability strip.
Identifications, positions, photometry, spectra, some pulsationalfeatures, other astrophysical parameters and literature for 302pulsating variable stars in the lower instability strip, near the ZAMS,are given. About 185 stars have near homogeneous photometric informationin the Stroemgren's uvby-β photometric system. Thiscatalogue/database covers information published until November 1993.

The radial velocities delta Sct-type star V474 Mon.
Not Available

Post-main-sequence and POST red giant branch variables with pulsation periods less than one day
Post-main-sequence (mass 1 to 3 solar masses) and post-giant branch (0.5to 1 solar mass) pulsators are discussed on the basis of four color andH beta light curves published elsewhere. The post-main-sequencevariables, called ultrashort period cepheid (USPC) (delta Sct), pulsatein the fundamental and first harmonic modes of radial pulsation and, inmany cases, in nonradial modes. The variables for which photometryallows accurate, luminosity estimates and are known to pulsatesimultaneously in the fundamental and first harmonic or in thefundamental mode alone, define a PL relation (MV = -2.80 logP - 0.60, fundamental). It is notable that the slope of this relation isin the range of slopes found for classical cepheids. Accurate Vphotometry is lacking for many of the variables known as 'anomalouscepheids', but the available data divide them into low mass,pseudocepheids (BL Her and W Vir stars) and post-main-sequence USPC(delta Sct) variables. Four USPC in NGC 5053 and six in NGC 6466, forwhich accurate photometry is available, give remarkably consistentmoduli of 16.06 +/- 0.05 and 15.98 +/- 0.08 mag, respectively, for theclusters, in which they are blue stragglers similar to SX Phe inKapteyn's star group. The assumption that the four post-giant branchvariables, called VSPC (RR Lyr), S Ari, SU Dra, and ST Leo in Kapteyn'sstar group and RR Lyr in the Groombridge 1830 group, are physicalmembers of these groups and share their V-velocities, leads to acalibration of the photometry for the derivation of reddening,luminosity, and heavy element abundance of 45 field variables. Theresulting reddenings are consistent with values obtained by othermethods and the metallicities are consistent with the most accuratelyavailable spectroscopic determinations of delta S and of Ca II K. Theluminosities of the bulk of the variables confirm Sandage's (1993)relation between MV and (Fe/H). Four or five of the fieldvariables are probably binary, including BB Vir which Kinman &Carreta (1992) have independently noted as double. The PL relation forUSPC (delta Sct) variables intersects the horizontal branch (HB) near P= 0.3d and at least two field very short period cepheid (VSPC) (RR Lyr)star, FW Lup (0.484 d) and ST Pic (0.486 d) may be first overtonepulsators of the USPC (delta Sct) variety. A dozen field VSPC (RR Lyr)stars populate a (Fe/H), MV relation with the same slope asthe other stars but displaced 0.7 mag toward higher luminosities. Theonly cluster variable found to populate this diplaced relation is No. 9in 47 Tuc, although ST Vir, which may be a member of the Arcturus group,should also be considered. The elevated luminosities are unlikely to becaused by either evolution or errors in the photometric indices. Apossible source of these apparently young VSPC(RR Lyr) variables withhalo metallicity is in second (or third) generation globular clustersformed during an episodic collapse of the galaxy that produced metalpoor stars but in a dynamical situation that hastened the disruption ofthe clusters, currently formed, before the still older globularclusters, created under conditions that have kept them in a moredisruptive free environment.

δ Scuti stars: a new revised list
An extensive and up to date list of δ Sct stars is presented. Thiscatalogue is intended to be a comprehensive review of observationalcharacteristics of all the δ Sct stars known until now, includingstars contained in earlier catalogues together with other new discoveredvariables, covering information published until November 1993. Globalinformation in the form of histograms and diagrams are also shown.

A new approach to the Cepheid period-luminosity law - Delta Scuti stars as small Cepheids
It is argued that the apparent separation of Delta Scuti stars andclassical Cepheids into two classes is due to a simple selection effect,and that Delta Sct stars and Cepheids are really a single class ofvariable star. The precision with which the P-L and other relations areknown can be greatly improved by combining the two classes.

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Takýmyýldýz:Tekboynuz
Sað Açýklýk:05h59m01.00s
Yükselim:-09°22'56.0"
Görünürdeki Parlaklýk:6.12
Uzaklýk:96.899 parsek
özdevim Sað Açýklýk:18.6
özdevim Yükselim:13.7
B-T magnitude:6.514
V-T magnitude:6.174

Kataloglar ve belirtme:
Özgün isimleri   (Edit)
Flamsteed1 Mon
HD 1989HD 40535
TYCHO-2 2000TYC 5352-932-1
USNO-A2.0USNO-A2 0750-01700726
BSC 1991HR 2107
HIPHIP 28321

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