{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.676","julian_year":2026.676,"time":"2026-09-04T22:31:28.678Z","years_from_j2000":26.676,"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-57117","name":"PGC 57117","class":"galaxy","category":"galaxy","object_type":"Galaxy","mag":15.115,"mag_band":"B","abs_mag":-19.831754271701946,"abs_mag_band":"B","distance_ly":318256094.9007941,"distance_method":"luminosity distance from a photometric redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":241.497803,"dec_deg":21.36035,"epoch_ra_deg":241.790984,"epoch_dec_deg":21.287322,"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":"Hercules","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-57117","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.115,"h_mag":12.299,"j_mag":12.952,"k_mag":12.023,"redshift":0.023889,"redshift_cmb":0.0224038388388538,"uncertainties":{"distance_ly":[70031103.49823736,70497369.11486122],"stellar_mass_solar":[6538900255.851258,6538900255.851258]},"stellar_mass_solar":10275414687.766264},"designations":[{"catalog":"2MASX","designation":"2MASX 16055947+2121372"},{"catalog":"PGC","designation":"PGC 57117"},{"catalog":"WISExSCOS","designation":"WISExSCOS J160559.50+212137.6"}],"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":"2026-09-02T19:50:56.720Z","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."}