{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.674","julian_year":2026.674,"time":"2026-09-04T08:25:37.047Z","years_from_j2000":26.674,"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-4913","name":"NGC 4913","class":"intermediate_spiral_galaxy_saba","category":"galaxy","object_type":"Intermediate spiral galaxy SABa","mag":13.84,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":350426591.2905502,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":195.43070833333334,"dec_deg":29.044666666666668,"epoch_ra_deg":195.75377,"epoch_dec_deg":28.900045,"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":"Coma Berenices","discovered":"1865","featured":false,"url":"https://spacecatalog.org/object/ngc-4913","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":14.71,"h_mag":10.99,"j_mag":11.7,"k_mag":10.72,"v_mag":13.84,"redshift":0.02373,"hubble_type":"SABa","wikidata_id":"Q1115512","redshift_cmb":0.024628087332446036,"discovered_by":"William Parsons, 3rd Earl of Rosse","ngc_type_code":"G","uncertainties":{"distance_ly":[20050743.455911182,20050743.455911182]},"major_axis_arcmin":1.45,"minor_axis_arcmin":0.4,"position_angle_deg":88,"surface_brightness":23.53,"radial_velocity_km_s":7030},"designations":[{"catalog":"2MASX","designation":"2MASX J13014338+2902407"},{"catalog":"IC","designation":"IC 4088"},{"catalog":"IC","designation":"IC 843"},{"catalog":"IRAS","designation":"IRAS F12593+2918"},{"catalog":"LEDA","designation":"LEDA 44908"},{"catalog":"LEDA","designation":"LEDA 44921"},{"catalog":"MCG","designation":"MCG +05-31-102"},{"catalog":"NGC","designation":"NGC 4913"},{"catalog":"PGC","designation":"PGC 44921"},{"catalog":"SDSS","designation":"SDSS J130143.36+290240.9"},{"catalog":"SDSS","designation":"SDSS J130143.37+290240.7"},{"catalog":"SDSS","designation":"SDSS J130143.37+290240.8"},{"catalog":"UGC","designation":"UGC 8140"}],"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."}