{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.670","julian_year":2026.67,"time":"2026-09-02T18:24:21.387Z","years_from_j2000":26.67,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued J2000 position is carried along the great circle the object's own published motion puts it on, at a constant velocity, and the result is referred to the true equator and equinox of this instant. Those are separate things: the motion moves the object, and the rotation turns the grid under it by about fifty arcseconds a year, with nutation adding up to another seventeen.","excluded":"Parallax, the radial-velocity perspective term, aberration and refraction; each is below the accuracy of the catalogued positions themselves. An object with no published proper motion comes back where the catalogue has it rather than at a fabricated zero, and says so with a null pm_ra_mas_yr. A body with no fixed position is not propagated at all — its place comes from an ephemeris, which is what /api/v1/visible answers with."},"slug":"pgc-51912","name":"PGC 51912","class":"spiral_galaxy_sc","category":"galaxy","object_type":"Spiral galaxy Sc","mag":15.146,"mag_band":"B","abs_mag":-17.45480966663353,"abs_mag_band":"B","distance_ly":108040804.28562964,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":217.968628,"dec_deg":8.933053,"epoch_ra_deg":218.298521,"epoch_dec_deg":8.814056,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Boötes","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-51912","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.146,"h_mag":13.223,"j_mag":13.981,"k_mag":13.11,"redshift":0.00724,"hubble_type":"Sc","redshift_cmb":0.007689606166283,"uncertainties":{"distance_ly":[6486471.796644555,6486898.247783737],"stellar_mass_solar":[93421507.09807865,93421507.09807865]},"major_axis_arcmin":0.773217,"minor_axis_arcmin":0.330395,"morphology_source":"SIMBAD (2015ApJS..217...27A, quality C)","position_angle_deg":89,"stellar_mass_solar":280264521.29423594},"designations":[{"catalog":"2MASX","designation":"2MASX 14315247+0855589"},{"catalog":"PGC","designation":"PGC 51912"},{"catalog":"WISExSCOS","designation":"WISExSCOS J143152.40+085558.6"}],"source":{"id":"glade_plus","name":"GLADE+ (Galaxy List for the Advanced Detector Era)","url":"https://cdsarc.cds.unistra.fr/viz-bin/cat/VII/291","license":"VizieR terms; cite Dalya+ 2022 (2022MNRAS.514.1403D)"},"updated_at":"2026-09-01T22:58:55.274Z","attribution":"Data from SpaceCatalog.org. Individual records carry their source and license in `source`; attribution is required for CC-BY and CC-BY-SA rows."}