{"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":"2026-09-03T13:06:19.845Z","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-3549","name":"NGC 3549","class":"barred_spiral_galaxy_sbc","category":"galaxy","object_type":"Barred spiral galaxy SBc","mag":12.14,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":142397779.2498051,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":167.73695833333332,"dec_deg":53.38777777777778,"epoch_ra_deg":168.125979,"epoch_dec_deg":53.242071,"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":"1789","featured":false,"url":"https://spacecatalog.org/object/ngc-3549","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.79,"h_mag":9.45,"j_mag":10.15,"k_mag":9.18,"v_mag":12.14,"redshift":0.0095,"hubble_type":"SBc","wikidata_id":"Q614225","redshift_cmb":0.010116387812518113,"discovered_by":"William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[15209055.090349676,15209055.090349676]},"major_axis_arcmin":2.64,"minor_axis_arcmin":0.86,"position_angle_deg":39,"surface_brightness":22.73,"radial_velocity_km_s":2835},"designations":[{"catalog":"2MASX","designation":"2MASX J11105690+5323155"},{"catalog":"IRAS","designation":"IRAS 11080+5339"},{"catalog":"IRAS","designation":"IRAS F11080+5339"},{"catalog":"LEDA","designation":"LEDA 33964"},{"catalog":"MCG","designation":"MCG +09-18-097"},{"catalog":"NGC","designation":"NGC 3549"},{"catalog":"PGC","designation":"PGC 33964"},{"catalog":"SDSS","designation":"SDSS J111056.86+532316.1"},{"catalog":"SDSS","designation":"SDSS J111056.87+532315.9"},{"catalog":"SDSS","designation":"SDSS J111056.87+532316.0"},{"catalog":"UGC","designation":"UGC 6215"}],"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."}