{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.664","julian_year":2026.664,"time":"2026-08-31T10:17:27.897Z","years_from_j2000":26.664,"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":"ic-356","name":"IC 356","class":"spiral_galaxy_sb","category":"galaxy","object_type":"Spiral galaxy Sb","mag":10.24,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":44649254.912276916,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":61.945458333333335,"dec_deg":69.81244444444444,"epoch_ra_deg":62.647057,"epoch_dec_deg":69.883984,"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":"Camelopardalis","discovered":"1889","featured":false,"url":"https://spacecatalog.org/object/ic-356","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":11.56,"h_mag":6.33,"j_mag":7.16,"k_mag":6.04,"v_mag":10.24,"redshift":0.003446,"hubble_type":"Sb","wikidata_id":"Q3713895","redshift_cmb":0.0031886794063877844,"discovered_by":"Edward Emerson Barnard","ngc_type_code":"G","uncertainties":{"distance_ly":[14127101.011302127,14127101.011302127]},"major_axis_arcmin":4.02,"minor_axis_arcmin":3.73,"position_angle_deg":90,"surface_brightness":23.27,"radial_velocity_km_s":1031},"designations":[{"catalog":"2MASX","designation":"2MASX J04074690+6948447"},{"catalog":"IC","designation":"IC 356"},{"catalog":"IRAS","designation":"IRAS 04025+6940"},{"catalog":"IRAS","designation":"IRAS 0402+696P02"},{"catalog":"IRAS","designation":"IRAS F04025+6940"},{"catalog":"LEDA","designation":"LEDA 14508"},{"catalog":"MCG","designation":"MCG +12-04-011"},{"catalog":"PGC","designation":"PGC 14508"},{"catalog":"UGC","designation":"UGC 2953"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}