COCD ivo://nasa.heasarc/cocd NASA/GSFC HEASARC Kharchenko et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The Catalog of Open Cluster Data (COCD) is a result of studies of the wide neighborhoods of 513 open clusters and 7 compact associations carried out in the high-precision homogeneous All-Sky Compiled Catalog of 2.5 Million Stars (ASCC-2.5, Kharchenko 2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/280B">CDS Cat. <I/280B></a>). On the basis of data on about 33,000 possible members (including about 10,000 most probable ones) and homogeneous methods of cluster parameter determination, the angular sizes of cluster cores and coronae, cluster heliocentric distances, mean proper motions, mean radial velocities and ages were established and collected in the COCD. These include cluster distances for 200 clusters, average cluster radial velocities for 94 clusters, and cluster ages for 195 clusters derived for the first time. Clusters in the catalogue are sequenced in their Right Ascension J2000 order. The Open Cluster Diagrams Atlas (OCDA) presents a set of open cluster diagrams used for the determination of parameters of the 513 open clusters and 7 compact associations, and is intended to illustrate the quality of the constructed cluster membership (Kharchenko et al. 2004, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AN/325/740">CDS Cat. <J/AN/325/740></a>), and the accuracy of the derived cluster parameters. Every diagram presents relation between various stellar data from the ASCC-2.5 in the area of the specific cluster. There are five diagrams provided for every cluster in the Atlas: the area map, the density profile, the vector point diagram, the magnitude equation diagram and the color-magnitude diagram. The OCDA PostScript plots (one file per cluster) are available as a remote data product for entries in this table. This table was created by the HEASARC in May 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/438/1163">CDS Catalog J/A+A/438/1163</a> files cocd.dat and notes.dat. This is a service provided by NASA HEASARC . 2005A&A...438.1163K https://heasarc.gsfc.nasa.gov/W3Browse/all/cocd.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=cocd& GET text/xml 180 99999 true 130.53 -79.03 0.5 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=cocd GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_cocd&Action=More+Options&Action=Parameter+Search&ConeAdd=1 STAR CATALOG 0.5 Optical public cocd COCD: Catalog of Open Cluster Data source_number Sequential Identification Number for Each Source in Catalog meta.id;src short nullable name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable cluster_radius Angular Radius of the Cluster degree phys.angSize;src double nullable "distance" Distance (pc) pc pos.distance short nullable log_age Logarithm of Average Age (in years) log(yr) time.age double nullable pm_lii Average Proper Motion in lii*cos(bii) mas/yr pos.pm;pos.galactic.lon double nullable lit_rad_vel_error Standard Error in the Radial Velocity from Literature km/s stat.error;spect.dopplerVeloc;pos.heliocentric double nullable e_bv Color-Excess mag phot.color.excess;em.opt.B;em.opt.V double nullable distance_modulus Apparent Distance Modulus mag phot.mag.distMod double nullable num_rad_vel_stars Number of Stars Used for RV Calculation meta.number short nullable lii Galactic Longitude degree pos.galactic.lon double nullable num_cluster_stars Number of the Most Probable (1-Sigma) Members meta.number short nullable rad_vel Average Radial Velocity km/s spect.dopplerVeloc;pos.heliocentric double nullable num_log_age_stars Number of Stars Used for Average Age Calculation meta.number short nullable pm_dec Average Proper Motion in Declination mas/yr pos.pm;pos.eq.dec double nullable rad_vel_error Standard Error in the Average Radial Velocity km/s stat.error;spect.dopplerVeloc;pos.heliocentric double nullable pm_ra Average Proper Motion in RA*cos(Dec) mas/yr pos.pm;pos.eq.ra double nullable pm_ra_error Standard Error in pm_RA mas/yr stat.error;pos.pm;pos.eq.ra double nullable pm_dec_error Standard Error in pm_Dec mas/yr stat.error;pos.pm;pos.eq.dec double nullable lit_log_age Logarithm of the Average Age from Literature log(yr) time.age double nullable ref_lit_log_age Number Indicates the Source of the Average Age from Literature meta.ref;time.age short nullable core_radius Angular Radius of the Core degree phys.angSize;src double nullable notes Notes Concerning the Source meta.note char nullable alt_name Other Designation of the Cluster meta.id char nullable pm_bii Average Proper Motion in bii mas/yr pos.pm;pos.galactic.lat double nullable ref_distance Number Indicates the Source of Distance and E(B-V) meta.ref;pos.distance short nullable bii Galactic Latitude degree pos.galactic.lat double nullable lit_rad_vel Radial Velocity from Literature km/s spect.dopplerVeloc;pos.heliocentric double nullable ref_lit_rad_vel Number Indicates the Source of the Radial Velocity from Literature meta.ref;spect.dopplerVeloc;pos.heliocentric short nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable