{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T12:39:52.842Z","years_from_j2000":26.672,"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-4256","name":"NGC 4256","class":"spiral_galaxy_sb","category":"galaxy","object_type":"Spiral galaxy Sb","mag":12.68,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":123768611.19505183,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":184.67954166666667,"dec_deg":65.89825,"epoch_ra_deg":185.000592,"epoch_dec_deg":65.749099,"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":"Draco","discovered":"1790","featured":false,"url":"https://spacecatalog.org/object/ngc-4256","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.68,"h_mag":8.52,"j_mag":9.23,"k_mag":8.25,"redshift":0.008456,"hubble_type":"Sb","wikidata_id":"Q1110214","redshift_cmb":0.008801619731702903,"discovered_by":"William Herschel","ngc_type_code":"G","uncertainties":{"distance_ly":[14929023.283169055,14929023.283169055]},"major_axis_arcmin":3.87,"minor_axis_arcmin":0.76,"wikipedia_article":"NGC 4256","position_angle_deg":41,"surface_brightness":23.31,"radial_velocity_km_s":2524},"designations":[{"catalog":"2MASX","designation":"2MASX J12184303+6553530"},{"catalog":"2MASX","designation":"2MASX J12184305+6553540"},{"catalog":"IRAS","designation":"IRAS 12163+6610"},{"catalog":"IRAS","designation":"IRAS F12163+6610"},{"catalog":"LEDA","designation":"LEDA 39568"},{"catalog":"MCG","designation":"MCG +11-15-045"},{"catalog":"NGC","designation":"NGC 4256"},{"catalog":"PGC","designation":"PGC 39568"},{"catalog":"SDSS","designation":"SDSS J121843.08+655353.6"},{"catalog":"SDSS","designation":"SDSS J121843.08+655353.7"},{"catalog":"UGC","designation":"UGC 7351"}],"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."}