{"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":"2026-09-05T01:52:41.771Z","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-2559","name":"NGC 2559","class":"barred_spiral_galaxy_sbc","category":"galaxy","object_type":"Barred spiral galaxy SBc","mag":11.33,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":84633803.4414227,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":124.27529166666666,"dec_deg":-27.45583333333333,"epoch_ra_deg":124.554542,"epoch_dec_deg":-27.538454,"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":"Puppis","discovered":"1837","featured":false,"url":"https://spacecatalog.org/object/ngc-2559","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":11.69,"h_mag":7.7,"j_mag":8.38,"k_mag":7.42,"v_mag":11.33,"redshift":0.005172,"hubble_type":"SBc","wikidata_id":"Q1049723","redshift_cmb":0.006031209735700038,"discovered_by":"John Frederick William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[14450352.20224016,14450352.20224016]},"major_axis_arcmin":2.81,"minor_axis_arcmin":1.34,"wikipedia_article":"NGC 2559","position_angle_deg":7,"surface_brightness":22.25,"radial_velocity_km_s":1546},"designations":[{"catalog":"2MASX","designation":"2MASX J08170607-2727209"},{"catalog":"ESO","designation":"ESO 494-041"},{"catalog":"ESO","designation":"ESO 494-41"},{"catalog":"ESO-LV","designation":"ESO-LV 494-0410"},{"catalog":"IRAS","designation":"IRAS 08150-2718"},{"catalog":"LEDA","designation":"LEDA 23222"},{"catalog":"MCG","designation":"MCG -04-20-003"},{"catalog":"NGC","designation":"NGC 2559"},{"catalog":"PGC","designation":"PGC 23222"},{"catalog":"UGCA","designation":"UGCA 136"}],"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."}