{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.674","julian_year":2026.674,"time":"2026-09-04T00:46:19.332Z","years_from_j2000":26.674,"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-4144","name":"NGC 4144","class":"intermediate_spiral_galaxy_sabc","category":"galaxy","object_type":"Intermediate spiral galaxy SABc","mag":11.61,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":182.49416666666667,"dec_deg":46.45716666666667,"epoch_ra_deg":182.833353,"epoch_dec_deg":46.307721,"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":"Ursa Major","discovered":"1788","featured":false,"url":"https://spacecatalog.org/object/ngc-4144","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":12.04,"h_mag":9.59,"j_mag":10.12,"k_mag":9.39,"v_mag":11.61,"redshift":0.00088,"hubble_type":"SABc","wikidata_id":"Q1109310","redshift_cmb":0.001589030774027611,"discovered_by":"William Herschel","ngc_type_code":"G","major_axis_arcmin":5.24,"minor_axis_arcmin":1,"wikipedia_article":"NGC 4144","position_angle_deg":103,"surface_brightness":23.01,"radial_velocity_km_s":264},"designations":[{"catalog":"2MASX","designation":"2MASX J12095860+4627258"},{"catalog":"IRAS","designation":"IRAS 12074+4644"},{"catalog":"IRAS","designation":"IRAS F12074+4644"},{"catalog":"LEDA","designation":"LEDA 38688"},{"catalog":"MCG","designation":"MCG +08-22-077"},{"catalog":"NGC","designation":"NGC 4144"},{"catalog":"PGC","designation":"PGC 38688"},{"catalog":"SDSS","designation":"SDSS J120958.41+462726.6"},{"catalog":"UGC","designation":"UGC 7151"}],"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."}