I/251ivo://CDS.VizieR/I/251CDSMa C.Feissel M.2013-07-02T14:04:46Z2013-07-02T14:04:04ZCDS support team

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

cds-question@unistra.froptical-observationcatalogsastrometryvery-long-baseline-interferometryThe International Celestial Reference Frame (ICRF), is intended for adoption be the International Astronomical Union (IAU) as the conventional celestial system, under the name International Celestial Reference System (ICRS). (See http://maia.usno.navy.mil/iauc19/iaures.html#B5). A Working Group on Reference Frames (WGRF), with the participation of International Earth Rotation Service (IERS), was appointed by the IAU to accomplish the task of constructing the ICRF. The WGRF set up a list of 608 extragalactic radio sources uniformly distributed on the sky and evaluated their J2000.0 Very Long Baseline Interferometry (VLBI) coordinates in the ICRS by applying a no rotation constraint with respect to an earlier realization of the IERS Celestial reference system, RSC(IERS) 95 C 02 . The first realization of the ICRF has J2000.0 coordinates of 608 objects and is named RSC(WGRF)95 R 01. Radio sources in RSC(WGRF)95 R 01 are divided into three categories (see file "guide.txt"): defining, candidate and other sources. In order to provide radio source coordinates to link to the Hipparcos stellar reference frame to the ICRS, the WGRF issued a shorter version of the ICRF, RSC(WGRF) 95 R 02. It is a subset of RSC(WGRF) 95 R 01 that contains J2000.0 coordinates of 253 radio sources covering the declination range -81 degrees to +85 degrees. The 212 defining sources of RSC(WGRF)95 R 01 included 17 Hipparcos link objects. An additional 41 other radio sources had to be added RSC(WGRF) 95 R 02 for the link. The median positional accuracy of RSC(WGRF) 95 R 02 is 0.4 mas. The other 357 sources of RSC(WGRF) 95 R 01 have coordinates with lower precision (median= 0.8 mas) but they are still consistent with the ICRS. The direction of the axes of the ICRF are consistent with those of the FK5 system within the uncertainties of the latter. On the basis of Fricke's (1982A&A...107L..13F) and Schwan (1988) considerations, the uncertainty of the pole position relative to the mean pole at J2000.0 is +/-50 mas. Studies by Morrison et al. (1990A&A...240..173M) and Lindegren et al. (1995A&A...304...44L) have shown that the FK5 origin of right ascensions has an uncertainty of the order of +/-100 mas. The accuracy of the tie of the Hipparcos stellar frame to ICRS is +/-0.6 mas at the Hipparcos mean epoch of observation (1991.25) and +/-0.25 mas/year for the time evolution. The tie between the dynamical planetary frame and ICRS is known within +/-3 mas (Folkner et al. 1994A&A...287..279F). Abstract of the 1998AJ....116..516M paper: A quasi-inertial reference frame is defined based on the radio positions of 212 extragalactic sources distributed over the entire sky. The positional accuracy of these sources is better than about 1mas in both coordinates. The radio positions are based upon a general solution for all applicable dual-frequency 2.3 and 8.4GHz Mark III very long baseline interferometry data available through the middle of 1995, consisting of 1.6 million pairs of group delay and phase delay rate observations. Positions and details are also given for an additional 396 objects that either need further observation or are currently unsuitable for the definition of a high-accuracy reference frame. The final orientation of the frame axes has been obtained by a rotation of the positions into the system of the International Celestial Reference System and is consistent with the FK5 J2000.0 optical system, within the limits of the link accuracy. The resulting International Celestial Reference Frame has been adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1998 January 1.1997AAS...191.1613Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/I/251CatalogResearchIsServedByTAP VizieR generic serviceIsPreviousVersionOfI/323IsServedByConesearch servicerelated-toI/218 : New Reference Frame defined by Extragalactic Radio SourceI/239 : The Hipparcos and Tycho Catalogues (ESA 1997)http://hpiers.obspm.fr/webiers/results/icrf/README.html : ICRF Home Pagehttp://aa.usno.navy.mil/AA/data/docs/ICRS_links.html : ICRS at USNOhttp://hpiers.obspm.fr/webiers/results/icrf/Updating.html : UpdatingTable 1: Summary of catalog differences (from 1998AJ....116..516M)Table 2: Alignment of the ICRF axes with the ICRS (from 1998AJ....116..516M)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=I/251https://vizier.iucaa.in/viz-bin/VizieR-2?-source=I/251http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=I/251https://vizier.cds.unistra.fr/viz-bin/votable?-source=I/251https://vizier.iucaa.in/viz-bin/votable?-source=I/251http://vizieridia.saao.ac.za/viz-bin/votable?-source=I/251GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table I/251/rsc95r01 (ICRF RSC(WGRF)95 R 01 all sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/I/251/rsc95r01?https://vizier.iucaa.in/viz-bin/conesearch/I/251/rsc95r01?http://vizieridia.saao.ac.za/viz-bin/conesearch/I/251/rsc95r01?GETtext/xml+votable180.050000true1.14856498333-47.605445433330.005555555555555556Cone search capability for table I/251/rsc95r02 (ICRF RSC(WGRF)95 R 02 subset)https://vizier.cds.unistra.fr/viz-bin/conesearch/I/251/rsc95r02?https://vizier.iucaa.in/viz-bin/conesearch/I/251/rsc95r02?http://vizieridia.saao.ac.za/viz-bin/conesearch/I/251/rsc95r02?GETtext/xml+votable180.050000true1.4882308708338.337541269440.0055555555555555566/60 110 124 180 198 304 307 421 532 556 579 593 700 839 911 1154 1200 1233 1521 1546 1622 1701 1702 1782 2098 2124 2143 2207 2245 2397 2414 2531 2600 2631 2710 2721 2836 2867 3024 3096 3309 3316 3402 3675 3820 3882 3886 3971 4027 4054 4436 4448 4572 4695 4696 4770 4820 4964 5154 5163 5306 5371 5423 5448 5458 5546 5597 5693 5766 5767 5817 5848 6033 6067 6104 6164 6167 6252 6377 6448 6496 6507 6548 6641 6686 6751 6790 6853 6948 6976 6996 7148 7181 7296 7345 7346 7351 7371 7389 7472 7570 7606 7623 7653 7745 7851 7857 7896 7969 8031 8057 8112 8123 8199 8299 8345 8487 8615 8717 8805 8858 8905 8915 8948 9125 9204 9347 9403 9442 9460 9512 9545 9588 9612 9632 9633 9655 9676 9681 9688 9711 9714 9720 9723 9813 9837 9976 10006 10163 10228 10249 10321 10422 10432 10440 10463 10466 10501 10548 10798 10803 10983 11094 11206 11216 11279 11430 11461 11639 11715 11845 11880 12047 12091 12173 12218 12301 12352 12475 12580 12599 12971 12987 13156 13213 13230 13352 13410 13496 13545 13693 13722 13789 13927 14150 14338 14348 14455 14520 14608 14634 14737 14842 15023 15036 15286 15373 15494 15536 15819 15936 15947 16027 16049 16059 16093 16113 16185 16261 16281 16298 16301 16302 16592 16962 17019 17110 17184 17188 17215 17351 17516 17529 17541 17579 17734 17791 17857 17909 18002 18022 18035 18037 18084 18214 18242 18271 18378 18457 18506 18545 18624 18661 18669 18718 18755 18871 18907 19088 19101 19166 19177 19190 19271 19370 19398 19523 19567 19609 19629 19831 19872 19918 20099 20213 20358 20468 20476 20500 20503 20657 20935 21012 21049 21117 21121 21163 21266 21358 21437 21508 21564 21758 21768 21924 21935 21960 21968 21972 22363 22375 22396 22501 22658 22659 22917 22943 22950 22965 23014 23022 23099 23121 23127 23197 23323 23333 23335 23383 23416 23478 23691 23761 23786 23805 23882 24003 24084 24099 24116 24123 24335 24453 24571 24608 24809 24845 25016 25083 25196 25255 25256 25302 25428 25493 25503 25630 25742 25864 25990 26000 26083 26100 26115 26131 26292 26301 26303 26363 26491 26550 26769 26900 26966 26983 27060 27220 27310 27322 27423 27466 27514 27583 27765 27909 27926 28167 28184 28208 28339 28383 28453 28454 28479 28492 28517 28628 28799 28897 29016 29218 29384 29570 29675 29714 29795 29963 30527 30657 31176 31190 31211 31334 31355 31391 31430 31451 31529 31535 31559 31664 31857 31894 32311 32325 32594 32660 32764 32841 32916 32948 32961 33010 33043 33048 33180 33549 33560 33626 33684 33825 33827 33829 33833 33973 34013 34038 34099 34123 34210 34264 34330 34428 34461 34517 34571 34572 34675 34699 34870 34871 34931 35079 35249 35294 35370 35440 35482 35491 35651 35786 35801 36155 36188 36417 36554 36785 36877 36941 37064 37201 37217 37385 37474 37480 37819 37919 37994 38128 38189 38277 38383 38416 38474 38579 38734 38763 39181 39235 39241 39377 39447 39489 39557 39577 39672 39695 39733 39848 40060 40344 40479 40527 40692 40730 40990 41059 41072 41088 41275 41310 41511 41578 41607 41665 41669 42060 42249 42366 42571 42853 42883 42901 42980 43195 43257 43262 43366 43399 43417 43566 43628 43694 43822 43936 44034 44043 44147 44247 44502 44614 44658 44661 44776 44805 44832 44899 44908 45110 45158 45162 45178 45196 45393 45409 45446 45612 45614 45621 45763 45774 45784 45795 46055 46174 46251 46310 46337 46373 46394 46459 46562 46588 46709 46762 46764 46851 46921 46931 46964 47014 47016 47080 47106 47107 47268 47375 47534 47540 47747 47941 48023 48123 48142 48228 48362 48589 48595 48610 48798 48846 48965https://cdsarc.cds.unistra.fr/viz-bin/moc/I/251?format=asciiOpticalRadiodefaultI/251/rsc95r01ICRF RSC(WGRF)95 R 01 all sourcesICRFICRF designationmeta.id;meta.maincharIERSIERS designationmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintc[DCO] Defining / Candidate / Other category of sourcemeta.notecharX? X band structure indexspect.index;em.X-rayintnullableS? S band structure indexspect.indexintnullableHip[* ] Link to Hipparcos reference framemeta.ref;pos.framecharRAJ2000Right Ascension (J2000) hourspos.eq.ra;meta.mainDEJ2000Declination (J2000) degreespos.eq.dec;meta.maine_RAJ2000Uncertainty in Right Ascensionsstat.error;pos.eq.radoublee_DEJ2000Uncertainty in Declinationarcsecstat.error;pos.eq.decdoubleCorr[-1,1]? RA/Dec correlationstat.correlationfloatnullableEpMean date of observation (JD)dtime.epochdoubleO1First date of observation (JD)dtime.epoch;obsdoubleOlLast Julian date of observation (JD)dtime.epoch;obsdoubleNsessNumber of observing sessionsmeta.numberintNdelNumber of delay, delay rate obs. pairsmeta.numberintI/251/rsc95r02ICRF RSC(WGRF)95 R 02 subsetICRFICRF designationmeta.id;meta.maincharIERSIERS designationmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintstatus[DL ] Status of sourcemeta.codecharRAJ2000Right Ascension (J2000) hourspos.eq.ra;meta.mainDEJ2000Declination (J2000) degreespos.eq.dec;meta.maine_RAJ2000Uncertainty in Right Ascensionsstat.error;pos.eq.radoublee_DEJ2000Uncertainty in Declinationarcsecstat.error;pos.eq.decdouble