{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.675","julian_year":2026.675,"time":"2026-09-04T15:46:42.436Z","years_from_j2000":26.675,"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-623","name":"NGC 623","class":"elliptical_galaxy_e","category":"galaxy","object_type":"Elliptical galaxy E","mag":12.52,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":416005369.0619644,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":23.776625000000003,"dec_deg":-36.49022222222222,"epoch_ra_deg":24.077533,"epoch_dec_deg":-36.352628,"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":"1837","featured":false,"url":"https://spacecatalog.org/object/ngc-623","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.55,"h_mag":9.83,"j_mag":10.56,"k_mag":9.59,"v_mag":12.52,"redshift":0.029871,"hubble_type":"E","wikidata_id":"Q1037734","redshift_cmb":0.0291403784852855,"discovered_by":"John Frederick William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[22021588.81169658,22021588.81169658]},"major_axis_arcmin":1.94,"minor_axis_arcmin":1.46,"wikipedia_article":"NGC 623","position_angle_deg":87,"surface_brightness":23.84,"radial_velocity_km_s":8821},"designations":[{"catalog":"2MASX","designation":"2MASX J01350638-3629248"},{"catalog":"ESO","designation":"ESO 353-023"},{"catalog":"ESO","designation":"ESO 353-23"},{"catalog":"ESO-LV","designation":"ESO-LV 353-0230"},{"catalog":"LEDA","designation":"LEDA 5898"},{"catalog":"MCG","designation":"MCG -06-04-052"},{"catalog":"NGC","designation":"NGC 623"},{"catalog":"PGC","designation":"PGC 5898"}],"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."}