HIPNEWCAT ivo://nasa.heasarc/hipnewcat NASA/GSFC HEASARC Van Leeuwen 2026-04-03 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Star A new reduction of the astrometric data as produced by the Hipparcos mission has been published, claiming accuracies for nearly all stars brighter than Hipparcos magnitude H_p = 8 to be better, by up to a factor 4, than in the original catalog. The new Hipparcos astrometric catalog has been checked for the quality of the data and the consistency of the formal errors as well as the possible presence of error correlations. The differences with the earlier publication of the Hipparcos Catalog are explained in the reference paper. The internal errors are followed through the reduction process, and the external errors are investigated on the basis of a comparison with radio observations of a small selection of stars, and the distribution of negative parallaxes. Error correlation levels are investigated and the reduction by more than a factor 10 as obtained in the new catalog is explained. The formal errors on the parallaxes for the new catalog are confirmed. The presence of a small amount of additional noise, though unlikely, cannot be ruled out. The new reduction of the Hipparcos astrometric data provides an improvement by a factor 2.2 in the total weight compared to the Hipparcos catalog published in 1997, and, according to the author, provides much improved data for a wide range of studies on stellar luminosities and local galactic kinematics. Note that this catalog version is slightly different from the one published in the book, as an error that sometimes affected the goodness of fit value for the solution was corrected. The first version of these data archived at the CDS (between June and 15 September 2008) also contained errors which were corrected after this date. This table was created by the HEASARC in August 2009 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/311">CDS Catalog I/311</a> file hip2.dat, "the Astrometric Catalogue". This is a service provided by NASA HEASARC . 2007A&A...474..653V https://heasarc.gsfc.nasa.gov/W3Browse/all/hipnewcat.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=hipnewcat& GET text/xml 180 99999 true 149.167260196041 -89.7824538212169 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=hipnewcat GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_hipnewcat&Action=More+Options&Action=Parameter+Search&ConeAdd=1 STAR CATALOG 0.0166666666666667 Optical public hipnewcat Hipparcos New Astrometric Catalog dec_error Formal Error in Declination mas stat.error;pos.eq.dec;meta.main double nullable var_data_annex Reference to Variability Annex [0,2] meta.code;src.var short nullable hip_mag_error Error in Mean Hipparcos Magnitude mag stat.error;phot.mag;em.IR.H double nullable number_components Number of Components meta.number short nullable pm_ra_error Formal Error in Proper Motion in Right Ascension mas/yr stat.error;pos.pm;pos.eq.ra double nullable quality_fit Goodness of Fit stat.fit.goodness double nullable "__z_ra_dec" System unit vector column double nullable dec Declination (ICRS, Epoch 1991.25) degree pos.eq.dec;meta.main double nullable hip_mag Hipparcos Magnitude mag phot.mag;em.opt.V double nullable scat_hip_mag Scatter of Mean Hipparcos Magnitude mag stat.variance;phot.mag double nullable suppl_cat_flag Flag Indicates Entry in One of the Supplemental Catalogs meta.note short nullable bv_color B-V Color Index mag phot.color;em.opt.B;em.opt.V double nullable bii Galactic Latitude degree pos.galactic.lat double nullable lii Galactic Longitude degree pos.galactic.lon double nullable pm_ra Proper Motion in Right Ascension mas/yr pos.pm;pos.eq.ra double nullable "__row" System index column char nullable parallax_error Formal Error in Parallax mas stat.error;pos.parallax double nullable ra_error Formal Error in Right Ascension mas stat.error;pos.eq.ra;meta.main double nullable pm_dec_error Formal Error in Proper Motion in Declination mas/yr stat.error;pos.pm;pos.eq.dec double nullable bv_color_error Formal Error in B-V Color Index mag stat.error;phot.color;em.opt.B;em.opt.V double nullable parallax Parallax mas pos.parallax double nullable ut_weight_matrix Upper-Triangular Weight Matrix meta.code;stat.fit char nullable hip_number Hipparcos Identifier meta.id int nullable ra Right Ascension (ICRS, Epoch 1991.25) degree pos.eq.ra;meta.main double nullable old_solution_type Solution Type Old Reduction [0,5] meta.id;stat.fit short nullable vi_color V-I Color Index mag phot.color;em.opt.V;em.opt.I double nullable cosmic_dispersion Cosmic Dispersion Added (Stochastic Solution) meta.code double nullable new_solution_type Solution Type New Reduction [0,159] meta.id;stat.fit short nullable pm_dec Proper Motion in Declination mas/yr pos.pm;pos.eq.dec double nullable n_obs_hip_mag Number of Field Transits Used meta.number;obs short nullable reject_percent Percentage Rejected Data percent stat.value;arith.ratio short nullable name Catalog Source Designation meta.id;meta.main char nullable "__y_ra_dec" System unit vector column double nullable "__x_ra_dec" System unit vector column double nullable