{"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":"2026-09-02T16:42:20.794Z","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-20928","name":"PGC 20928","class":"spiral_galaxy_s","category":"galaxy","object_type":"Spiral galaxy S","mag":15.429,"mag_band":"B","abs_mag":-19.359802593785055,"abs_mag_band":"B","distance_ly":295928228.2385325,"distance_method":"luminosity distance from a photometric redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":111.10807,"dec_deg":38.945309,"epoch_ra_deg":111.565187,"epoch_dec_deg":38.893068,"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":"Auriga","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-20928","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.429,"h_mag":13.703,"j_mag":14.153,"k_mag":13.265,"redshift":0.020863,"hubble_type":"S","redshift_cmb":0.0208559058214083,"uncertainties":{"distance_ly":[61228602.53491291,61583809.39725455],"stellar_mass_solar":[934137689.6442794,934137689.6442794]},"major_axis_arcmin":0.792583,"minor_axis_arcmin":0.336055,"morphology_source":"SIMBAD (2018MNRAS.477.4711G, quality E)","position_angle_deg":93,"stellar_mass_solar":1868275379.2885587},"designations":[{"catalog":"2MASX","designation":"2MASX 07242593+3856431"},{"catalog":"PGC","designation":"PGC 20928"},{"catalog":"WISExSCOS","designation":"WISExSCOS J072425.85+385643"}],"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."}