{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.671","julian_year":2026.671,"time":"2026-09-03T01:55:40.469Z","years_from_j2000":26.671,"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-564","name":"NGC 564","class":"elliptical_galaxy_e","category":"galaxy","object_type":"Elliptical galaxy E","mag":12.51,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":257361390.95901048,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":21.950875,"dec_deg":-1.879527777777778,"epoch_ra_deg":22.293196,"epoch_dec_deg":-1.740184,"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":"Cetus","discovered":"1785","featured":false,"url":"https://spacecatalog.org/object/ngc-564","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.52,"h_mag":9.89,"j_mag":10.54,"k_mag":9.6,"v_mag":12.51,"redshift":0.019203,"hubble_type":"E","wikidata_id":"Q578763","redshift_cmb":0.018173969260300238,"discovered_by":"William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[17558660.019724,17558660.019724]},"major_axis_arcmin":1.72,"minor_axis_arcmin":1.2,"wikipedia_article":"NGC 564","position_angle_deg":141,"surface_brightness":23.55,"radial_velocity_km_s":5702},"designations":[{"catalog":"2MASX","designation":"2MASX J01274822-0152465"},{"catalog":"LEDA","designation":"LEDA 5455"},{"catalog":"MCG","designation":"MCG +00-04-154"},{"catalog":"NGC","designation":"NGC 564"},{"catalog":"PGC","designation":"PGC 5455"},{"catalog":"UGC","designation":"UGC 1044"}],"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."}