{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T16:48:03.465Z","years_from_j2000":26.681,"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-3400128","name":"PGC 3400128","class":"galaxy","category":"galaxy","object_type":"Galaxy","mag":16.91,"mag_band":"B","abs_mag":-17.919005789327198,"abs_mag_band":"B","distance_ly":301458152.394292,"distance_method":"luminosity distance from a photometric redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":165.651,"dec_deg":50.67886,"epoch_ra_deg":166.042457,"epoch_dec_deg":50.534398,"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":"Ursa Major","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-3400128","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":16.91,"h_mag":13.72,"j_mag":14.395,"k_mag":13.539,"redshift":0.0221909210955,"redshift_cmb":0.0212396035481503,"uncertainties":{"distance_ly":[65015197.92287,65417714.16794467],"stellar_mass_solar":[1868270898.6308234,1868270898.6308234]},"stellar_mass_solar":4670677246.577059},"designations":[{"catalog":"2MASX","designation":"2MASX 11023629+5040438"},{"catalog":"Other","designation":"2MASXJ11023629+5040438"},{"catalog":"PGC","designation":"PGC 3400128"},{"catalog":"WISExSCOS","designation":"WISExSCOS J110236.32+504043.8"}],"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."}