{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T14:37:40.432Z","years_from_j2000":26.672,"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-3889","name":"NGC 3889","class":"elliptical_galaxy_e_s0","category":"galaxy","object_type":"Elliptical galaxy E-S0","mag":15.55,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":803840436.2896761,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":176.95054166666668,"dec_deg":56.01833333333333,"epoch_ra_deg":177.309062,"epoch_dec_deg":55.869143,"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":"Ursa Major","discovered":"1878","featured":false,"url":"https://spacecatalog.org/object/ngc-3889","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.55,"h_mag":11.68,"j_mag":12.34,"k_mag":11.52,"redshift":0.05468,"hubble_type":"E-S0","wikidata_id":"Q1107005","redshift_cmb":0.0552625118599257,"discovered_by":"Lawrence Parsons, 4th Earl of Rosse","ngc_type_code":"G","uncertainties":{"distance_ly":[35504255.31703124,35504255.31703124]},"major_axis_arcmin":0.73,"minor_axis_arcmin":0.41,"position_angle_deg":123,"surface_brightness":23.63,"radial_velocity_km_s":15945},"designations":[{"catalog":"2MASX","designation":"2MASX J11474814+5601062"},{"catalog":"LEDA","designation":"LEDA 36662"},{"catalog":"LEDA","designation":"LEDA 36819"},{"catalog":"MCG","designation":"MCG +09-19-191"},{"catalog":"NGC","designation":"NGC 3889"},{"catalog":"PGC","designation":"PGC 36819"},{"catalog":"SDSS","designation":"SDSS J114748.11+560106.3"},{"catalog":"SDSS","designation":"SDSS J114748.12+560106.0"},{"catalog":"SDSS","designation":"SDSS J114748.13+560105.9"},{"catalog":"SDSS","designation":"SDSS J114748.13+560106.0"}],"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."}