{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T13:40:28.102Z","years_from_j2000":26.667,"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":"ic-4913","name":"IC 4913","class":"elliptical_galaxy_e_s0","category":"galaxy","object_type":"Elliptical galaxy E-S0","mag":13.98,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":163912461.8802855,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":299.19849999999997,"dec_deg":-37.328361111111114,"epoch_ra_deg":299.642501,"epoch_dec_deg":-37.256959,"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":"Sagittarius","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/ic-4913","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.98,"h_mag":10.02,"j_mag":10.74,"k_mag":9.81,"redshift":0.01219,"hubble_type":"E-S0","wikidata_id":"Q3681032","redshift_cmb":0.011631612072615871,"ngc_type_code":"G","uncertainties":{"distance_ly":[15571222.36199029,15571222.36199029]},"major_axis_arcmin":1.57,"minor_axis_arcmin":1.07,"position_angle_deg":127,"surface_brightness":23.69,"radial_velocity_km_s":3631},"designations":[{"catalog":"2MASX","designation":"2MASX J19564762-3719422"},{"catalog":"ESO","designation":"ESO 399-005"},{"catalog":"ESO","designation":"ESO 399-5"},{"catalog":"ESO-LV","designation":"ESO-LV 399-0050"},{"catalog":"IC","designation":"IC 4913"},{"catalog":"LEDA","designation":"LEDA 63850"},{"catalog":"MCG","designation":"MCG -06-43-013"},{"catalog":"PGC","designation":"PGC 63850"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"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."}