{"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":"2026-09-04T09:41:50.116Z","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-6658","name":"NGC 6658","class":"lenticular_galaxy_s0_a","category":"galaxy","object_type":"Lenticular galaxy S0-a","mag":11.8,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":187072912.85395688,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":278.48187500000006,"dec_deg":22.888277777777777,"epoch_ra_deg":278.763387,"epoch_dec_deg":22.908429,"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":"Hercules","discovered":"1864","featured":false,"url":"https://spacecatalog.org/object/ngc-6658","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.85,"h_mag":9.78,"j_mag":10.6,"k_mag":9.51,"v_mag":11.8,"redshift":0.013719,"hubble_type":"S0-a","wikidata_id":"Q1146932","redshift_cmb":0.013258951963587062,"discovered_by":"Albert Marth","ngc_type_code":"G","uncertainties":{"distance_ly":[16004419.217995858,16004419.217995858]},"major_axis_arcmin":1.5,"minor_axis_arcmin":0.25,"position_angle_deg":5,"surface_brightness":22.31,"radial_velocity_km_s":4085},"designations":[{"catalog":"2MASX","designation":"2MASX J18335567+2253178"},{"catalog":"LEDA","designation":"LEDA 62052"},{"catalog":"MCG","designation":"MCG +04-44-002"},{"catalog":"NGC","designation":"NGC 6658"},{"catalog":"PGC","designation":"PGC 62052"},{"catalog":"UGC","designation":"UGC 11274"}],"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."}