{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.670","julian_year":2026.67,"time":"2026-09-02T16:08:42.429Z","years_from_j2000":26.67,"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-954","name":"NGC 954","class":"barred_spiral_galaxy_sbc","category":"galaxy","object_type":"Barred spiral galaxy SBc","mag":12.91,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":245118846.55659056,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":37.215125,"dec_deg":-41.40266666666667,"epoch_ra_deg":37.480969,"epoch_dec_deg":-41.282441,"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":"Eridanus","discovered":"1834","featured":false,"url":"https://spacecatalog.org/object/ngc-954","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.59,"h_mag":10.55,"j_mag":11.15,"k_mag":10.08,"v_mag":12.91,"redshift":0.01783,"hubble_type":"SBc","wikidata_id":"Q1040473","redshift_cmb":0.01732043156424745,"discovered_by":"John Frederick William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[17264648.77206271,17264648.77206271]},"major_axis_arcmin":1.79,"minor_axis_arcmin":0.94,"position_angle_deg":16,"surface_brightness":23.05,"radial_velocity_km_s":5298},"designations":[{"catalog":"2MASX","designation":"2MASX J02285162-4124095"},{"catalog":"ESO","designation":"ESO 299-004"},{"catalog":"ESO","designation":"ESO 299-4"},{"catalog":"ESO-LV","designation":"ESO-LV 299-0040"},{"catalog":"IRAS","designation":"IRAS 02268-4137"},{"catalog":"LEDA","designation":"LEDA 9438"},{"catalog":"MCG","designation":"MCG -07-06-006"},{"catalog":"NGC","designation":"NGC 954"},{"catalog":"PGC","designation":"PGC 9438"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","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."}