{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-01T21:21:50.894Z","years_from_j2000":26.668,"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-172","name":"NGC 172","class":"barred_spiral_galaxy_sbbc","category":"galaxy","object_type":"Barred spiral galaxy SBbc","mag":13.52,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":129808605.42131357,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":9.306708333333335,"dec_deg":-22.587027777777777,"epoch_ra_deg":9.641449,"epoch_dec_deg":-22.43922,"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":"Cetus","discovered":"1886","featured":false,"url":"https://spacecatalog.org/object/ngc-172","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":14.09,"h_mag":11.41,"j_mag":12.1,"k_mag":11.15,"v_mag":13.52,"redshift":0.010234,"hubble_type":"SBbc","wikidata_id":"Q1035659","redshift_cmb":0.009228179257962932,"discovered_by":"Frank Muller","ngc_type_code":"G","uncertainties":{"distance_ly":[15016282.106441665,15016282.106441665]},"major_axis_arcmin":2.04,"minor_axis_arcmin":0.4,"wikipedia_article":"NGC 172","position_angle_deg":14,"surface_brightness":23.16,"radial_velocity_km_s":3052},"designations":[{"catalog":"2MASX","designation":"2MASX J00371359-2235132"},{"catalog":"ESO","designation":"ESO 474-005"},{"catalog":"ESO","designation":"ESO 474-5"},{"catalog":"ESO-LV","designation":"ESO-LV 474-0050"},{"catalog":"IRAS","designation":"IRAS 00348-2251"},{"catalog":"LEDA","designation":"LEDA 2228"},{"catalog":"MCG","designation":"MCG -04-02-027"},{"catalog":"NGC","designation":"NGC 172"},{"catalog":"PGC","designation":"PGC 2228"}],"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."}