{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.673","julian_year":2026.673,"time":"2026-09-03T19:55:50.611Z","years_from_j2000":26.673,"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-4402","name":"NGC 4402","class":"spiral_galaxy_sb","category":"galaxy","object_type":"Spiral galaxy Sb","mag":11.78,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":186.53187499999999,"dec_deg":13.113333333333333,"epoch_ra_deg":186.872427,"epoch_dec_deg":12.964591,"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":"1862","featured":false,"url":"https://spacecatalog.org/object/ngc-4402","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.78,"h_mag":8.63,"j_mag":9.6,"k_mag":8.49,"v_mag":11.78,"redshift":0.00077,"hubble_type":"Sb","wikidata_id":"Q1111211","redshift_cmb":0.0018673868901784019,"discovered_by":"Arthur Auwers","ngc_type_code":"G","major_axis_arcmin":3.52,"minor_axis_arcmin":1,"wikipedia_article":"NGC 4402","position_angle_deg":89,"surface_brightness":23.38,"radial_velocity_km_s":231},"designations":[{"catalog":"2MASX","designation":"2MASX J12260756+1306460"},{"catalog":"IRAS","designation":"IRAS 12235+1323"},{"catalog":"IRAS","designation":"IRAS F12235+1323"},{"catalog":"LEDA","designation":"LEDA 40644"},{"catalog":"MCG","designation":"MCG +02-32-044"},{"catalog":"NGC","designation":"NGC 4402"},{"catalog":"PGC","designation":"PGC 40644"},{"catalog":"SDSS","designation":"SDSS J122607.65+130647.9"},{"catalog":"SDSS","designation":"SDSS J122607.71+130649.0"},{"catalog":"UGC","designation":"UGC 7528"}],"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."}