{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T04:16:59.955Z","years_from_j2000":26.669,"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":"ngc-439","name":"NGC 439","class":"elliptical_galaxy_e_s0","category":"galaxy","object_type":"Elliptical galaxy E-S0","mag":12.89,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":259724392.08325964,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":18.44691666666667,"dec_deg":-31.74713888888889,"epoch_ra_deg":18.762844,"epoch_dec_deg":-31.604744,"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":"Sculptor","discovered":"1834","featured":false,"url":"https://spacecatalog.org/object/ngc-439","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.89,"h_mag":9,"j_mag":9.62,"k_mag":8.7,"redshift":0.019173,"hubble_type":"E-S0","wikidata_id":"Q926937","redshift_cmb":0.018338593128056857,"discovered_by":"John Frederick William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[17616432.562520288,17616432.562520288]},"major_axis_arcmin":3.38,"minor_axis_arcmin":2.14,"wikipedia_article":"NGC 439","position_angle_deg":156,"surface_brightness":24.24,"radial_velocity_km_s":5693},"designations":[{"catalog":"2MASX","designation":"2MASX J01134725-3144500"},{"catalog":"ESO","designation":"ESO 412-018"},{"catalog":"ESO","designation":"ESO 412-18"},{"catalog":"ESO-LV","designation":"ESO-LV 412-0180"},{"catalog":"LEDA","designation":"LEDA 4423"},{"catalog":"MCG","designation":"MCG -05-04-015"},{"catalog":"NGC","designation":"NGC 439"},{"catalog":"PGC","designation":"PGC 4423"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"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."}