{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.673","julian_year":2026.673,"time":"2026-09-03T22:32:04.969Z","years_from_j2000":26.673,"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-2271","name":"NGC 2271","class":"elliptical_galaxy_e_s0","category":"galaxy","object_type":"Elliptical galaxy E-S0","mag":13.18,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":128440005.0489585,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":100.72079166666667,"dec_deg":-23.476,"epoch_ra_deg":101.000868,"epoch_dec_deg":-23.501918,"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":"Canis Major","discovered":"1835","featured":false,"url":"https://spacecatalog.org/object/ngc-2271","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.18,"h_mag":8.95,"j_mag":9.69,"k_mag":8.68,"redshift":0.008633,"hubble_type":"E-S0","wikidata_id":"Q1047827","redshift_cmb":0.009131549042719511,"discovered_by":"John Frederick William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[14996208.934467841,14996208.934467841]},"major_axis_arcmin":1.77,"minor_axis_arcmin":1.29,"position_angle_deg":78,"surface_brightness":23.18,"radial_velocity_km_s":2577},"designations":[{"catalog":"2MASX","designation":"2MASX J06425299-2328333"},{"catalog":"ESO","designation":"ESO 490-034"},{"catalog":"ESO","designation":"ESO 490-34"},{"catalog":"ESO-LV","designation":"ESO-LV 490-0340"},{"catalog":"LEDA","designation":"LEDA 19476"},{"catalog":"MCG","designation":"MCG -04-16-017"},{"catalog":"NGC","designation":"NGC 2271"},{"catalog":"PGC","designation":"PGC 19476"}],"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."}