{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.665","julian_year":2026.665,"time":"2026-08-31T22:36:23.075Z","years_from_j2000":26.665,"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-9947","name":"PGC 9947","class":"galaxy","category":"galaxy","object_type":"Galaxy","mag":15.1,"mag_band":"B","abs_mag":-20.567075279039564,"abs_mag_band":"B","distance_ly":443446193.2036388,"distance_method":"luminosity distance from a photometric redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":39.402271,"dec_deg":1.605545,"epoch_ra_deg":39.748959,"epoch_dec_deg":1.722223,"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":"Cetus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-9947","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.1,"h_mag":12.512,"j_mag":13.235,"k_mag":12.244,"redshift":0.030032,"redshift_cmb":0.0310199631909002,"uncertainties":{"distance_ly":[89462690.52084944,90189149.78931491],"stellar_mass_solar":[7472624424.329724,7472624424.329724]},"stellar_mass_solar":12143014689.5358},"designations":[{"catalog":"2MASX","designation":"2MASX 02373654+0136199"},{"catalog":"PGC","designation":"PGC 9947"},{"catalog":"WISExSCOS","designation":"WISExSCOS J023736.56+013619.5"}],"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":"2026-08-30T09:56:50.739Z","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."}