{"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":"2026-09-02T21:35:10.495Z","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-1553","name":"PGC 1553","class":"spiral_galaxy_sc","category":"galaxy","object_type":"Spiral galaxy Sc","mag":15.055,"mag_band":"B","abs_mag":-19.631377244766142,"abs_mag_band":"B","distance_ly":282293789.78935,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":6.181875,"dec_deg":21.101055,"epoch_ra_deg":6.531425,"epoch_dec_deg":21.24987,"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":"Pisces","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-1553","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.055,"h_mag":11.699,"j_mag":12.508,"k_mag":11.347,"redshift":0.01789,"hubble_type":"Sc","redshift_cmb":0.0199089594572867,"uncertainties":{"distance_ly":[15199786.189518515,15202543.539072135],"stellar_mass_solar":[9341432517.13712,9341432517.13712]},"major_axis_arcmin":0.625673,"minor_axis_arcmin":0.293003,"morphology_source":"SIMBAD (2003A&A...412...45P, quality E)","position_angle_deg":116,"stellar_mass_solar":18682865034.27424},"designations":[{"catalog":"2MASX","designation":"2MASX 00244365+2106037"},{"catalog":"PGC","designation":"PGC 1553"},{"catalog":"WISExSCOS","designation":"WISExSCOS J002443.69+210603.8"}],"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":"2026-09-02T19:50:56.720Z","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."}