{"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":"2026-09-04T23:35:34.918Z","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":"ngc-6338","name":"NGC 6338","class":"lenticular_galaxy_s0","category":"galaxy","object_type":"Lenticular galaxy S0","mag":12.42,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":387175083.41578287,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":258.8457916666667,"dec_deg":57.41119444444444,"epoch_ra_deg":258.961211,"epoch_dec_deg":57.380171,"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":"Draco","discovered":"1789","featured":false,"url":"https://spacecatalog.org/object/ngc-6338","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.47,"h_mag":9.7,"j_mag":10.39,"k_mag":9.4,"v_mag":12.42,"redshift":0.0273,"hubble_type":"S0","wikidata_id":"Q1145165","redshift_cmb":0.02716021749803832,"discovered_by":"William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[21137144.3806601,21137144.3806601]},"major_axis_arcmin":1.73,"minor_axis_arcmin":1.04,"wikipedia_article":"NGC 6338","position_angle_deg":16,"surface_brightness":23.38,"radial_velocity_km_s":8073},"designations":[{"catalog":"2MASX","designation":"2MASX J17152291+5724404"},{"catalog":"LEDA","designation":"LEDA 59947"},{"catalog":"MCG","designation":"MCG +10-24-116"},{"catalog":"NGC","designation":"NGC 6338"},{"catalog":"PGC","designation":"PGC 59947"},{"catalog":"SDSS","designation":"SDSS J171522.96+572440.5"},{"catalog":"SDSS","designation":"SDSS J171522.97+572440.2"},{"catalog":"SDSS","designation":"SDSS J171522.98+572440.2"},{"catalog":"SDSS","designation":"SDSS J171522.99+572440.2"},{"catalog":"SDSS","designation":"SDSS J171522.99+572440.3"},{"catalog":"UGC","designation":"UGC 10784"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"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."}