{"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":"2026-09-03T05:04:02.827Z","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-4301","name":"NGC 4301","class":"spiral_galaxy_sc","category":"galaxy","object_type":"Spiral galaxy Sc","mag":13.12,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":76389556.17598896,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":185.61337500000002,"dec_deg":4.566277777777778,"epoch_ra_deg":185.956408,"epoch_dec_deg":4.417323,"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":"Virgo","discovered":"1851","featured":false,"url":"https://spacecatalog.org/object/ngc-4301","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.53,"h_mag":11.94,"j_mag":12.14,"k_mag":11.2,"v_mag":13.12,"redshift":0.00429,"hubble_type":"Sc","wikidata_id":"Q1110541","redshift_cmb":0.005446116279409718,"discovered_by":"William Parsons, 3rd Earl of Rosse","ngc_type_code":"G","uncertainties":{"distance_ly":[14369537.516474007,14369537.516474007]},"major_axis_arcmin":1.14,"minor_axis_arcmin":1.09,"wikipedia_article":"NGC 4301","position_angle_deg":15,"surface_brightness":22.51,"radial_velocity_km_s":1283},"designations":[{"catalog":"2MASX","designation":"2MASX J12222724+0433586"},{"catalog":"IRAS","designation":"IRAS 12198+0450"},{"catalog":"LEDA","designation":"LEDA 40087"},{"catalog":"MCG","designation":"MCG +01-32-027"},{"catalog":"NGC","designation":"NGC 4301"},{"catalog":"NGC","designation":"NGC 4303A"},{"catalog":"PGC","designation":"PGC 40087"},{"catalog":"UGC","designation":"UGC 7439"}],"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."}