I/259ivo://CDS.VizieR/I/259CDSHog E.Fabricius C.Makarov V.V.Urban S.Corbin T.,Wycoff G.Bastian U.Schwekendiek P.Wicenec A.2000-02-07T22:00:40Z2000-02-07T16:24:04ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frastrometryproper-motionssurveysphotometrymultiple-starsThe Tycho-2 Catalogue is an astrometric reference catalogue containing positions and proper motions as well as two-colour photometric data for the 2.5 million brightest stars in the sky. The Tycho-2 positions and magnitudes are based on precisely the same observations as the original Tycho Catalogue (hereafter Tycho-1; see Cat. <I/239>)) collected by the star mapper of the ESA Hipparcos satellite, but Tycho-2 is much bigger and slightly more precise, owing to a more advanced reduction technique. Components of double stars with separations down to 0.8 arcsec are included. Proper motions precise to about 2.5 mas/yr are given as derived from a comparison with the Astrographic Catalogue and 143 other ground-based astrometric catalogues, all reduced to the Hipparcos celestial coordinate system. Tycho-2 supersedes in most applications Tycho-1, as well as the ACT (Cat. <I/246>) and TRC (Cat. <I/250>) catalogues based on Tycho-1. Supplement-1 lists stars from the Hipparcos and Tycho-1 Catalogues which are not in Tycho-2. Supplement-2 lists 1146 Tycho-1 stars which are probably either false or heavily disturbed. For more information, please consult the Tycho-2 home page: http://www.astro.ku.dk/~erik/Tycho-2 Catalogue Characteristics: The principal characteristics of the Tycho-2 Catalogue are summarized below. By means of proper motions the positions are transferred to the year 2000.0, the epoch of the catalogue. The median values of internal standard errors are given. ------------------------------------------------------------ Mean satellite observation epoch ~J1991.5 Epoch of the Tycho-2 Catalogue J2000.0 Reference system ICRS coincidence with ICRS (1) +/-0.6 mas deviation from inertial (1) +/-0.25 mas/yr Number of entries 2,539,913 Astrometric standard errors (2) V_T_ < 9 mag 7 mas all stars, positions 60 mas all stars, proper motions 2.5 mas/yr Photometric std. errors (3) on V_T_ V_T_ < 9 mag 0.013 mag all stars 0.10 mag Star density b= 0 deg 150 stars/sq.deg. b= +/-30 deg 50 stars/sq.deg. b= +/-90 deg 25 stars/sq.deg. Completeness to 90 per cent V ~ 11.5 mag Completeness to 99 per cent V ~ 11.0 mag Number of Tycho observations ~300 10^6^ ------------------------------------------------------------ Note (1): about all 3 axes Note (2): ratio of external to internal standard errors is ~1.0 for positions and for proper motions. Systematic errors are less than 1 mas and 0.5 mas/yr Note (3): ratio of photometric external to internal standard errors at V_T_ > 9 mag is below 1.5 ------------------------------------------------------------2000A&A...355L..27Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/I/259CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/239 : The Hipparcos and Tycho Catalogues (ESA 1997)I/211 : CCDM (Components of Double and Multiple stars) (Dommanget+ 1994)I/246 : The ACT Reference Catalog (Urban+ 1997)I/250 : The Tycho Reference Catalogue (Hog+ 1998)http://www.astro.ku.dk/~erik/Tycho-2 : Tycho-2 home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=I/259https://vizier.iucaa.in/viz-bin/VizieR-2?-source=I/259http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=I/259https://vizier.cds.unistra.fr/viz-bin/votable?-source=I/259https://vizier.iucaa.in/viz-bin/votable?-source=I/259http://vizieridia.saao.ac.za/viz-bin/votable?-source=I/259GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table I/259/tyc2 (*The Tycho-2 main catalogue)https://vizier.cds.unistra.fr/viz-bin/conesearch/I/259/tyc2?https://vizier.iucaa.in/viz-bin/conesearch/I/259/tyc2?http://vizieridia.saao.ac.za/viz-bin/conesearch/I/259/tyc2?GETtext/xml+votable180.050000true2.317542222.231864440.005555555555555556Hips catalogue for table I/259/tyc2https://hipscat.cds.unistra.fr/HiPSCatService/I/259/tyc2Cone search capability for table I/259/suppl_1 (The Tycho-2 supplement-1)https://vizier.cds.unistra.fr/viz-bin/conesearch/I/259/suppl_1?https://vizier.iucaa.in/viz-bin/conesearch/I/259/suppl_1?http://vizieridia.saao.ac.za/viz-bin/conesearch/I/259/suppl_1?GETtext/xml+votable180.050000true3.037088711.573514770.005555555555555556Cone search capability for table I/259/suppl_2 (The Tycho-2 supplement-2)https://vizier.cds.unistra.fr/viz-bin/conesearch/I/259/suppl_2?https://vizier.iucaa.in/viz-bin/conesearch/I/259/suppl_2?http://vizieridia.saao.ac.za/viz-bin/conesearch/I/259/suppl_2?GETtext/xml+votable180.050000true14.759456812.665261790.005555555555555556Hipparcos0/0 1 2 3 4 5 6 7 8 9 10 11https://cdsarc.cds.unistra.fr/viz-bin/moc/I/259?format=asciiOpticaldefaultI/259/tyc2*The Tycho-2 main cataloguerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTYC1[1,9537]+= TYC1 from TYC or GSC (1)meta.id.part;meta.mainintprimaryindexedTYC2[1,12121] TYC2 from TYC or GSC (1)meta.id.part;meta.mainintprimaryindexedTYC3[1,3] TYC3 from TYC (1)meta.id.part;meta.mainintprimaryindexedpflag[ PX] mean position flag (2)meta.codecharRAmdeg[]? Mean Right Asc, ICRS, epoch=J2000 (3)degpos.eq.ranullableDEmdeg[]? Mean Decl, ICRS, at epoch=J2000 (3)degpos.eq.decnullablepmRA[-4418.0,6544.2]? prop. mot. in RA*cos(dec)mas/yrpos.pm;pos.eq.rafloatnullablepmDE[-5774.3,10277.3]? prop. mot. in Decmas/yrpos.pm;pos.eq.decfloatnullablee_RAmdeg[3,183]? s.e. RA*cos(dec),at mean epoch (5)masstat.errorintnullablee_DEmdeg[1,184]? s.e. of Dec at mean epoch (5)masstat.errorintnullablee_pmRA[0.2,11.5]? s.e. prop mot in RA*cos(dec)(5)mas/yrstat.errorfloatnullablee_pmDE[0.2,10.3]? s.e. of proper motion in Dec(5)mas/yrstat.errorfloatnullableEpRAm[1915.95,1992.53]? mean epoch of RA (4)yrtime.epochfloatnullableEpDEm[1911.94,1992.01]? mean epoch of Dec (4)yrtime.epochfloatnullableNum[2,36]? Number of positions usedmeta.idintnullableq_RAmdeg[0.0,9.9]? Goodness of fit for mean RA (6)meta.code.qualfloatnullableq_DEmdeg[0.0,9.9]? Goodness of fit for mean Dec (6)meta.code.qualfloatnullableq_pmRA[0.0,9.9]? Goodness of fit for pmRA (6)meta.code.qualfloatnullableq_pmDE[0.0,9.9]? Goodness of fit for pmDE (6)meta.code.qualfloatnullableBTmag[2.183,16.581]? Tycho-2 BT magnitude (7)magphot.mag;em.opt.Bfloatnullablee_BTmag[0.014,1.977]? s.e. of BT (7)magstat.errorfloatnullableVTmag[1.905,15.193]? Tycho-2 VT magnitude (7)magphot.mag;em.opt.Vfloatnullablee_VTmag[0.009,1.468]? s.e. of VT (7)magstat.errorfloatnullableprox[3,999] proximity indicator (8)meta.codeintTYC[T] Tycho-1 star (9)meta.codecharHIP[1,120404]? Hipparcos numbermeta.idintnullableCCDMCCDM component identifier for HIP stars(10)meta.code.multipcharRA(ICRS)Observed Tycho-2 Right Ascension, ICRSdegpos.eq.ra;meta.mainindexedDE(ICRS)Observed Tycho-2 Declination, ICRSdegpos.eq.dec;meta.mainindexedEpRA-1990[0.81,2.13] epoch-1990 of RAdegyrtime.epochfloatEpDE-1990[0.72,2.36] epoch-1990 of DEdegyrtime.epochfloate_RAdegs.e.RA*cos(dec), of observed Tycho-2 RA (5)masstat.errorfloate_DEdegs.e. of observed Tycho-2 Dec (5)masstat.errorfloatposflg[ DP] type of Tycho-2 solution (11)meta.id;stat.fitcharcorr[-1,1] correlation (RAdeg,DEdeg)stat.correlationfloatI/259/suppl_1The Tycho-2 supplement-1recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTYC1[2,9529]+= TYC1 from TYC (1)meta.id.part;meta.mainintprimaryindexedTYC2[1,12112] TYC2 from TYC (1)meta.id.part;meta.mainintprimaryindexedTYC3[1,4] TYC3 from TYC (1)meta.id.part;meta.mainintprimaryindexedflag[HT] data from Hipparcos or Tycho-1 (2)meta.refcharRA(ICRS)Right Asc, ICRS, at epoch=J1991.25degpos.eq.ra;meta.mainDE(ICRS)Decl, ICRS, at epoch=J1991.25degpos.eq.dec;meta.mainpmRA[]? prop. mot. in RA*cos(dec)mas/yrpos.pm;pos.eq.rafloatnullablepmDE[]? prop. mot. in Decmas/yrpos.pm;pos.eq.decfloatnullablee_RAdegs.e. RA*cos(dec)masstat.errorfloate_DEdegs.e. of Decmasstat.errorfloate_pmRA[]? s.e. prop mot in RA * cos(dec)mas/yrstat.errorfloatnullablee_pmDE[]? s.e. of proper motion in Decmas/yrstat.errorfloatnullablemflag[ BVH] (3)meta.codecharBTmag[]? Tycho-1 BT magnitude (4)magphot.mag;em.opt.Bfloatnullablee_BTmag[]? s.e. of BT (4)magstat.errorfloatnullableVTmag[]? Tycho-1 VT or Hp magnitude (4)magphot.mag;em.opt.Vfloatnullablee_VTmag[]? s.e. of VT (4)magstat.errorfloatnullableprox[1,999] proximity indicator (5)meta.codeintTYC[ T] Tycho-1 starmeta.codecharHIP[1,120404]? Hipparcos numbermeta.idintnullableCCDMCCDM component identifier for HIP starsmeta.code.multipcharI/259/suppl_2The Tycho-2 supplement-2recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinte_BTmag[]? s.e. of BT (4)magstat.errorfloatnullableTYC1[2,9529]+= TYC1 from TYC (1)meta.id.part;meta.mainintprimaryindexedTYC2[1,12112] TYC2 from TYC (1)meta.id.part;meta.mainintprimaryindexedTYC3[1,4] TYC3 from TYC (1)meta.id.part;meta.mainintprimaryindexedflag[HT] data from Hipparcos or Tycho-1 (2)meta.refcharRA(ICRS)Right Asc, ICRS, at epoch=J1991.25degpos.eq.ra;meta.mainDE(ICRS)Decl, ICRS, at epoch=J1991.25degpos.eq.dec;meta.mainpmRA[]? prop. mot. in RA*cos(dec)mas/yrpos.pm;pos.eq.rafloatnullablepmDE[]? prop. mot. in Decmas/yrpos.pm;pos.eq.decfloatnullablee_RAdegs.e. RA*cos(dec)masstat.errorfloate_DEdegs.e. of Decmasstat.errorfloate_pmRA[]? s.e. prop mot in RA * cos(dec)mas/yrstat.errorfloatnullablee_pmDE[]? s.e. of proper motion in Decmas/yrstat.errorfloatnullablemflag[ BVH] (3)meta.codecharBTmag[]? Tycho-1 BT magnitude (4)magphot.mag;em.opt.BfloatnullableVTmag[]? Tycho-1 VT or Hp magnitude (4)magphot.mag;em.opt.Vfloatnullablee_VTmag[]? s.e. of VT (4)magstat.errorfloatnullableprox[1,999] proximity indicator (5)meta.codeintTYC[ T] Tycho-1 starmeta.codecharHIP[1,120404]? Hipparcos numbermeta.idintnullableCCDMCCDM component identifier for HIP starsmeta.code.multipchar