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AKARI's infrared view on nearby stars. Using AKARI infrared camera all-sky survey, 2MASS, and Hipparcos catalogs
Context. The AKARI, a Japanese infrared space mission, has performed anAll-Sky Survey in six infrared-bands from 9 to 180 ?m with higherspatial resolutions and better sensitivities than IRAS. Aims: Weinvestigate the mid-infrared (9 and 18 ?m) point source catalog (PSC)obtained with the infrared camera (IRC) onboard AKARI, in order tounderstand the infrared nature of the known objects and to identifypreviously unknown objects. Methods: Color-color diagramsand a color-magnitude diagram were plotted with the AKARI-IRC PSCand other available all-sky survey catalogs. We combined the Hipparcosastrometric catalog and the 2MASS all-sky survey catalog with theAKARI-IRC PSC. We furthermore searched literature and SIMBADastronomical database for object types, spectral types, and luminosityclasses. We identified the locations of representative stars and objectson the color-magnitude and color-color diagram schemes. Theproperties of unclassified sources can be inferred from their locationson these diagrams. Results: We found that the (B-V) vs.(V-S9W) color-color diagram is useful for identifying thestars with infrared excess emerged from circumstellar envelopes ordisks. Be stars with infrared excess are separated well from other typesof stars in this diagram. Whereas (J-L18W) vs. (S9W-L18W)diagram is a powerful tool for classifying several object types.Carbon-rich asymptotic giant branch (AGB) stars and OH/IR stars formdistinct sequences in this color-color diagram. Young stellarobjects (YSOs), pre-main sequence (PMS) stars, post-AGB stars, andplanetary nebulae (PNe) have the largest mid-infrared color excess andcan be identified in the infrared catalog. Finally, we plot the L18W vs.(S9W-L18W) color-magnitude diagram, using the AKARI data togetherwith Hipparcos parallaxes. This diagram can be used to identify low-massYSOs and AGB stars. We found that this diagram is comparable to the [24]vs. ([8.0]-[24]) diagram of Large Magellanic Cloud sources usingthe Spitzer Space Telescope data. Our understanding of Galactic objectswill be used to interpret color-magnitude diagram of stellar populationsin the nearby galaxies that Spitzer Space Telescope observed. Conclusions: Our study of the AKARI color-color andcolor-magnitude diagrams will be used to explore properties ofunknown objects in the future. In addition, our analysis highlights afuture key project to understand stellar evolution with a circumstellarenvelope, once the forthcoming astronometrical data with GAIA areavailable.Catalog (full Tables 3 and 4) are only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/514/A2
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Infrared photometry and evolution of mass-losing AGB stars. I. Carbon stars revisited
As part of a reanalysis of galactic Asymptotic Giant Branch (AGB) starsat infrared (IR) wavelengths, we discuss a sample (357) of carbon starsfor which mass loss rates, near-IR photometry and distance estimatesexist. For 252 sources we collected mid-IR fluxes from the MSX (6C) andthe ISO-SWS catalogues. Most stars have spectral energy distributions upto 21 μm, and some (1/3) up to 45 μm. This wide wavelengthcoverage allows us to obtain reliable bolometric magnitudes. Theproperties of our sample are discussed with emphasis on ~70 stars withastrometric distances. We show that mid-IR fluxes are crucial toestimate the magnitude of stars with dusty envelopes. We construct HRdiagrams and show that the luminosities agree fairly well with modelpredictions based on the Schwarzschild's criterion, contrary to what iswidely argued in the literature. A problem with the brightness of Cstars does not appear to exist. From the relative number of Mira andSemiregular C-variables, we argue that the switch between these classesis unlikely to be connected to thermal pulses. The relevance of the twopopulations varies with the evolution, with Miras dominating the finalstages. We also analyze mass loss rates, which increase for increasingluminosity, but with a spread that probably results from a dependence ona number of parameters (like e.g. different stellar masses and differentmechanisms powering stellar winds). Instead, mass loss rates are wellmonitored by IR colours, especially if extended to 20 μm and beyond,where AGB envelopes behave like black bodies. From these colours theevolutionary status of various classes of C stars is discussed.
| Oxygen-rich AGB stars with optically thin dust envelopes
The dust composition and dynamics of the circumstellar envelopes ofoxygen-rich AGB stars with low mass-loss rates (5 ×10-8-10-5 Mȯ yr-1) havebeen investigated. We have analyzed the ISO-SWS spectra of twenty-eightoxygen-rich AGB stars with optically thin shells, and modelled theobservations with the radiative transfer code DUSTY using the opticalconstants from laboratory dust analogues. This has allowed us todetermine the composition of the dust and the physical conditions at theinner edge of the shell. Moreover, by comparing with CO observationsavailable in the literature, we have determined the gas-to-dust massratios and the mass-loss rates of these sources, and analyzed thewind-driving mechanism. The results show that the small amounts of dustpresent in these envelopes, characterized by visual optical depths inthe 0.03-0.6 range, are enough to drive the wind by radiation pressureon the grains. In some sources there are indications of circumstellardust that does not contribute to the wind-driving, and that maydistributed in a disk or clumps. Other sources show signs of variablemass-loss rates. A grain mixture in the shell consisting of aluminiumoxide, melilite, olivine, spinel and Mg{0.1}Fe{0.9}O fit the observedspectra well. From these species, only melilite is required to have afractional abundance greater than 25% in all cases. Although spinelreproduces the 13 μm feature, the absence of the 16.8 μm peak inour SWS spectra casts doubts on this identification. The outcome of themodelling reveals that the olivine content in these CSEs increases withpressure and temperature at the inner edge. Moreover, the aluminiumoxide percentage in the dust of the envelopes shows a positivecorrelation with the gas-to-dust mass ratio. These results, togetherwith the derived dust compositions, are consistent with thethermodynamic dust condensation sequence scenario and its freezing-outdue to kinetics. However, the temperatures at the inner edge of theshell are substantially lower than those predicted by theory.
| Guilt by Association: The 13 Micron Dust Emission Feature and Its Correlation to Other Gas and Dust Features
A study of all full-scan spectra of optically thin oxygen-richcircumstellar dust shells in the database produced by the ShortWavelength Spectrometer on ISO reveals that the strength of severalinfrared spectral features correlates with the strength of the 13 μmdust feature. These correlated features include dust features at 19.8and 28.1 μm and the bands produced by warm carbon dioxide molecules(the strongest of which are at 13.9, 15.0, and 16.2 μm). The databasedoes not provide any evidence for a correlation of the 13 μm featurewith a dust feature at 32 μm, and it is more likely that a weakemission feature at 16.8 μm arises from carbon dioxide gas ratherthan dust. The correlated dust features at 13, 20, and 28 μm tend tobe stronger with respect to the total dust emission in semiregular andirregular variables associated with the asymptotic giant branch than inMira variables or supergiants. This family of dust features also tendsto be stronger in systems with lower infrared excesses and thus lowermass-loss rates. We hypothesize that the dust features arise fromcrystalline forms of alumina (13 μm) and silicates (20 and 28 μm).Based on observations with the ISO, a European Space Agency (ESA)project with instruments funded by ESA member states (especially thePrincipal Investigator countries: France, Germany, the Netherlands, andthe United Kingdom) and with the participation of the Institute of Spaceand Astronautical Science (ISAS) and the National Aeronautics and SpaceAdministration (NASA).
| Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable 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/qcat?J/A+A/397/997
| Classification of 2.4-45.2 Micron Spectra from the Infrared Space Observatory Short Wavelength Spectrometer
The Infrared Space Observatory observed over 900 objects with the ShortWavelength Spectrometer in full-grating scan mode (2.4-45.2 μm). Wehave developed a comprehensive system of spectral classification usingthese data. Sources are assigned to groups based on the overall shape ofthe spectral energy distribution (SED). The groups include naked stars,dusty stars, warm dust shells, cool dust shells, very red sources, andsources with emission lines but no detected continuum. These groups arefurther divided into subgroups based on spectral features that shape theSED such as silicate or carbon-rich dust emission, silicate absorption,ice absorption, and fine-structure or recombination lines. Caveatsregarding the data and data reduction, as well as biases intrinsic tothe database, are discussed. We also examine how the subgroups relate tothe evolution of sources to and from the main sequence and how thisclassification scheme relates to previous systems. Based on observationswith the Infrared Space Observatory (ISO), a European Space Agency (ESA)project with instruments funded by ESA Member States (especially thePrinciple Investigator countries: France, Germany, Netherlands, andUnited Kingdom) and with the participation of the Institute of Space andAstronautical Science and the National Aeronautics and SpaceAdministration (NASA).
| High Angular Resolution Observations of Late-Type Stars
This paper presents speckle observations of Mira (o Cet) and late-typestars with the PISCO speckle camera of Pic du Midi during the period1995-1998. A survey for binarity among a sample of late-type stars wasperformed, which led to seven positive detections out of 36 objects.Photometric and color variations of the companion of Mira were searchedfor, but no significant brightness variations could be found over atimescale of ~5-10 minutes. The position and photometry measurements,the restored images with high angular resolution of the binary systemMira A-B (ADS 1778) are in full agreement with Hubble Space Telescopedata obtained at the same epoch. A new orbit has been derived for MiraA-B.
| Long period variable stars: galactic populations and infrared luminosity calibrations
In this paper HIPPARCOS astrometric and kinematic data are used tocalibrate both infrared luminosities and kinematical parameters of LongPeriod Variable stars (LPVs). Individual absolute K and IRAS 12 and 25luminosities of 800 LPVs are determined and made available in electronicform. The estimated mean kinematics is analyzed in terms of galacticpopulations. LPVs are found to belong to galactic populations rangingfrom the thin disk to the extended disk. An age range and a lower limitof the initial mass is given for stars of each population. A differenceof 1.3 mag in K for the upper limit of the Asymptotic Giant Branch isfound between the disk and old disk galactic populations, confirming itsdependence on the mass in the main sequence. LPVs with a thin envelopeare distinguished using the estimated mean IRAS luminosities. The levelof attraction (in the classification sense) of each group for the usualclassifying parameters of LPVs (variability and spectral types) isexamined. Table 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/374/968 or via ASTRIDdatabase (http://astrid.graal.univ-montp2.fr).
| Stars with the Largest Hipparcos Photometric Amplitudes
A list of the 2027 stars that have the largest photometric amplitudes inHipparcos Photometry shows that most variable stars are all Miras. Thepercentage of variable types change as a function of amplitude. Thiscompilation should also be of value to photometrists looking forrelatively unstudied, but large amplitude stars.
| Infrared Properties of SiO Maser Sources in Late-Type Stars
The results of an SiO maser survey for late-type stars selected by theIRTS (Infrared Telescope in Space) are presented. We have detected SiOJ=1-0, v=1 and/or v=2 lines in 27 stars out of 59 stars. The maserintensity increases with the depth of the H_2O absorption in theinfrared spectra and redness of the 2.2 and 12 mu m color. The columndensities of the water vapor in the target stars were estimated from thedepth of the water absorption in the IRTS spectra. We found that the SiOmaser was detected mostly in the stars with a column density of watervapor higher than 3*E19-3*E20 cm-2. Wefurther estimated the density of hydrogen molecules in the outeratmosphere corresponding to these column densities, obtaining109-1010 cm-3 as a lower limit. Thesevalues are roughly in agreement with the critical hydrogen densitypredicted by models for the excitation of SiO masers. It is possiblethat the SiO masers are excited in clumps with column density evenhigher than this value. The present results provide useful informationfor the understanding of the physical conditions of the outeratmospheres in late-type stars.
| Period-Luminosity-Colour distribution and classification of Galactic oxygen-rich LPVs. I. Luminosity calibrations
The absolute K magnitudes and kinematic parameters of about 350oxygen-rich Long-Period Variable stars are calibrated, by means of anup-to-date maximum-likelihood method, using Hipparcos parallaxes andproper motions together with radial velocities and, as additional data,periods and V-K colour indices. Four groups, differing by theirkinematics and mean magnitudes, are found. For each of them, we alsoobtain the distributions of magnitude, period and de-reddened colour ofthe base population, as well as de-biased period-luminosity-colourrelations and their two-dimensional projections. The SRa semiregulars donot seem to constitute a separate class of LPVs. The SRb appear tobelong to two populations of different ages. In a PL diagram, theyconstitute two evolutionary sequences towards the Mira stage. The Mirasof the disk appear to pulsate on a lower-order mode. The slopes of theirde-biased PL and PC relations are found to be very different from theones of the Oxygen Miras of the LMC. This suggests that a significantnumber of so-called Miras of the LMC are misclassified. This alsosuggests that the Miras of the LMC do not constitute a homogeneousgroup, but include a significant proportion of metal-deficient stars,suggesting a relatively smooth star formation history. As a consequence,one may not trivially transpose the LMC period-luminosity relation fromone galaxy to the other Based on data from the Hipparcos astrometrysatellite. Appendix B is only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Infrared spectra of evolved stars with unusual dust shells
New mid-infrared spectra are presented of a number of oxygen-richevolved stars which have IRAS LRS (Low Resolution Spectrometer) spectrathat were classified as showing SiC emission. Two of the sources,IRC-20445 and IRC-20461, show the unidentified infrared (UIR) bandssuperposed on silicate emission features. Both objects have beenclassified as M supergiants. Several other sources show three-componentspectra, with peaks at 10, 11 and 13μm. The 13-μm source FI Lyrshows a narrow emission feature at 19μm. Emission by oxide grains maybe responsible for the 11-, 13- and 19-μm features. One object,IRC-20455, shows a self-absorbed silicate feature. There is no clearevidence for SiC emission in any of the spectra: the LRS spectra wereerroneously classified as showing SiC emission because of the relativelystrong 11-μm emission.
| The Infrared Spectral Classification of Oxygen-rich Dust Shells
This paper presents infrared spectral classifications for a flux-limitedsample of 635 optically identified oxygen-rich variables includingsupergiants and sources on the asymptotic giant branch (AGB). Severalclasses of spectra from oxygen-rich dust exist, and these can bearranged in a smoothly varying sequence of spectral shapes known as thesilicate dust sequence. Classification based on this sequence revealsseveral dependencies of the dust emission on the properties of thecentral star. Nearly all S stars show broad emission features fromalumina dust, while most of the supergiants exhibit classic featuresfrom amorphous silicate dust. Mira variables with symmetric light curvesgenerally show broad alumina emission, while those with more asymmetriclight curves show classic silicate emission. These differences may arisefrom differences in the photospheric C/O ratio.
| Classification and Identification of IRAS Sources with Low-Resolution Spectra
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.
| New infrared carbon stars in the IRAS point source catalog.
We present new results of a search for infrared carbon stars (IRCS)based on the combination of IRAS and near infrared colours. A sample of207 stars with IRAS colours that characterize IRCS is selected andmeasured in the $JHKL$ photometric bands. Using a [12 - 25] vs. K - Lcolour diagram, 20 new IRCS candidates are proposed. Medium resolutionspectra in the ~ 6000-9000 Angstrom range of 8 of these candidatesconfirm their carbon rich nature. In addition we propose a few starswith LRS class "4n" as oxygen--rich candidates, and a few stars with LRSclasses "0n" and "1n" as carbon-rich. Based on observations obtained atthe Observatoire de Haute Provence, France. Tables 2 and 3 are onlyavailable 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
| More (on) red giants with unusual dust shells.
Twenty-four M- and MS-stars have been suggested in the literature toshow the silicon carbide feature, indicative of a carbon-richcircumstellar shell. By cross-correlating the IRAS LRS atlas withBidelman's compilation of spectral types for objects in the IRC survey,this sample is enlarged to 39 sources. By carefully examining the LRSspectra, it appears that only one source shows silicon carbide emission.However, there is doubt on the correct association of this IRC sourcewith the IRAS source and on the spectral type of the IRC source. Theremaining objects are shown to have no dust, featureless dust, to showthe characteristic silicate feature at 18μm, or to display a broadfeature from 10-14μm which is known from previous studies on the dustaround M-stars. I conclude that based on the present sample there is noor weak evidence that silicon carbide dust forms in the shells around M-and MS-stars.
| A search for variability in the IRAS-LRS spectra of long period variables
Time-averaged IRAS-low resolution spectrometer (LRS) spectra have beenextensively used in the past for the study of mass loss in cool stars.Using the GEISHA system available at Groningen, we have extracted theraw LRS data for a sample of 40 mass losing asymptotic giant branch(AGB) stars. The selection was made on the basis of the number ofindividual spectra obtained by IRAS, the flux at 12 micrometers, an LRSclassification of 2n or 4n and a known association with an optical longperiod variable (Miras, Semiregulars). The spectra were analyzed inthree different ways, one of them being similar to the original LRSclassification scheme. Using spectra taken within 24 hours we estimatedthe internal accuracy of a single spectrum as a function of the 12micrometer flux. The spectra were then searched for variability in thesilicate and SiC dust features. Only one possible case of variabilitywas found. The results are discussed in terms of the pulsational andmass loss characteristics of our sample and other observational data oncircumstellar dust features.
| New OH/IR stars from color-selected IRAS sources. 3: A complete survey
We present the results of 1612 MHz observations conducted at the AreciboObservatory of 571 color-selected sources from the IRAS Point SourceCatalog. Of these sources we detect 132, 113 for the first time. This isthe third part of an Arecibo survey of color-selected IRAS sources. Theearlier two parts together detected a total of 268 sources of 1612 MHzemission. An analysis of the properties of the OH/IR stars detected inall three parts of the survey is included. In particular we compute thelimiting 1612 MHz peak flux of the entire survey to be approximately 40mJy. The correlation between the IRAS infrared fluxes and the 1612 MHzflux of the 132 sources detected in part III of the survey is smallerthan that found in the earlier parts of the survey. This is to beexpected from the intrinsic variability of OH/IR stars and the longertime gap between the 1612 MHz observations and the IRAS measurements. Weidentify a subset of 54 stars as being near the tangent point of thegalactic rotation curve. Using the kinematical distances to these starswe find that the efficiency of momentum transfer varies exponentiallywith the (25 - 12) micrometer color, consistent with the stellar outflowbeing driven by radiation pressure. Further the IR pump efficiencyincreases with increasing optical depth of the circumstellar shell, asexpected for radiative pumping. The bolometric luminosity function isfound to decrease sharply above LBol = 5600 solar luminosity,and the 1612 MHz luminosity function shows a corresponding falloff aboveL1612 = 1.8 x 10-8 solar luminosity. We also finddirect confirmation of the expectation that sources with large expansionvelocity are more luminous than sources with small expansion velocity.
| CO and HCN observations of circumstellar envelopes. A catalogue - Mass loss rates and distributions
We have searched the literature for all observations of the (C-12)O(1-0), (C-12)O (2-1), and HCN (1-0) lines in circumstellar envelopes oflate type stars published between January 1985 and September 1992. Wereport data for 1361 observations (stellar velocity, expansion velocity,peak intensity, integrated area, noise level). This CO-HCN sample nowcontains 444 sources; 184 are identified as O-rich, 205 as C-rich, andthere are 9 S stars. About 85 percent of the sources are AGB stars.There are 32 planetary nebulae and about thirty post-AGB starscandidates. Besides results of mm-observations, we also listidentifications, coordinates, IRAS data, and chemical and spectral typesfor every source. For AGB stars, we have estimated (or compiled)bolometric fluxes and distances for 349 sources, and mass loss ratesdeduced from CO results for 324 sources, taking into account theinfluence of the CO photodissociation radius. We also list mass lossrates derived from detailed models of CO emission in the literature.
| OH/IR star color mimics
IR color criteria are used to select potential OH/IR stars from the IRASPoint Source Catalog. These OH/IR star color mimics, despite oftenhaving thick and demonstrably O-rich dust shells to shield theirmolecules against interstellar UV, have no 1612 MHz masers. The mostlikely reason for this is that these stars have degenerate companions,which collect an accretion disk from the red giant wind, which in turnprovides them with a local source of UV to dissociate molecules fromwithin their dust shells. In some cases this self-generated UV issufficient to excise all molecules from a shell, as happens withsymbiotic novae; in some cases it merely reduces their number and theability of a shell to support a maser. It is suggested that D-typesymbiotic stars can be identified among sources with thick opaque dustshells by a persistent absence of appropriate masers: these are theOH/IR color mimics.
| A survey of circumstellar CO emission from a sample of IRAS point sources
The first results from a survey of circumstellar CO(1-0) emission arepresented. The sources were selected from the IRAS point source catalogaccording to the IRAS color criteria described in van der Veen andHabing (1988). The sources have good quality fluxes at 12, 25, and 60microns, flux densities larger than 20 Jy at 25 microns, and aresituated more than 5 deg away from the Galactic plane. The survey isundertaken to study the relationship between mass loss rates, dustproperties, and the evolution along the AGB. The sample consists of 787sources and contains both oxygen and carbon-rich stars, including Miravariables, OH/IR objects, protoplanetary nebulae, planetary nebulae, and60-micron excess sources. So far, 519 objects, situated on both thenorthern and the southern sky, have been observed; 163 sources werefound to have circumstellar CO emission, and in 58 of these CO emissionhas not previously been detected.
| Search for stars with intrinsic polarization
Results of polarimetric observations of 55 late-type stars arepresented. Twenty of these stars were found to have appreciablepolarization. The dependence of the degree of polarization on wavelengthis given. It is considered very probable that the polarizations of thestars SAO 141881, 141898, and 160413 are intrinsic.
| IRAS catalogues and atlases - Atlas of low-resolution spectra
Plots of all 5425 spectra in the IRAS catalogue of low-resolutionspectra are presented. The catalogue contains the average spectra ofmost IRAS poiont sources with 12 micron flux densities above 10 Jy.
| Suggested Identifications for Infrared Sources
Not Available
| Variable Stars in the Lyra Constellation
Not Available
| Classification of 831 two-micron sky survey sources south of +5 degrees.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80.1011H&db_key=AST
| Characteristics of OH emission from infrared stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&A....17..385W&db_key=AST
| The kinematics of semiregular red variables in the solar neighbourhood.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972MNRAS.158...23F&db_key=AST
| Spectral Types and Radiometric Observations of Stars of Large Infrared Index.
Not Available
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Dades d'Observació i Astrometria
| Constel·lació: | Lyra |
| Ascensió Recta: | 18h42m04.83s |
| Declinació: | +28°57'29.8" |
| Magnitud Aparent: | 9.589 |
| Distancia: | 641.026 parsecs |
| Moviment propi RA: | -5.6 |
| Moviment propi Dec: | 13.4 |
| B-T magnitude: | 11.087 |
| V-T magnitude: | 9.713 |
Catàlegs i designacions:
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