{"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":"2026-09-04T17:58:00.350Z","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-3158","name":"NGC 3158","class":"elliptical_galaxy_e","category":"galaxy","object_type":"Elliptical galaxy E","mag":11.88,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":340467335.6339808,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":153.4605,"dec_deg":38.76488888888889,"epoch_ra_deg":153.8594,"epoch_dec_deg":38.631911,"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":"Leo Minor","discovered":"1787","featured":false,"url":"https://spacecatalog.org/object/ngc-3158","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.89,"h_mag":9.1,"j_mag":9.81,"k_mag":8.8,"v_mag":11.88,"redshift":0.02309,"hubble_type":"E","wikidata_id":"Q1103275","redshift_cmb":0.023940269351790278,"discovered_by":"William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[19765119.878488634,19765119.878488634]},"major_axis_arcmin":2.32,"minor_axis_arcmin":1.94,"position_angle_deg":152,"surface_brightness":23.59,"radial_velocity_km_s":6842},"designations":[{"catalog":"2MASX","designation":"2MASX J10135049+3845536"},{"catalog":"LEDA","designation":"LEDA 29822"},{"catalog":"MCG","designation":"MCG +07-21-020"},{"catalog":"NGC","designation":"NGC 3158"},{"catalog":"PGC","designation":"PGC 29822"},{"catalog":"SDSS","designation":"SDSS J101350.51+384553.6"},{"catalog":"SDSS","designation":"SDSS J101350.52+384553.6"},{"catalog":"UGC","designation":"UGC 5511"}],"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."}