{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T17:17:08.330Z","years_from_j2000":26.678,"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-4137","name":"NGC 4137","class":"spiral_galaxy_sc","category":"galaxy","object_type":"Spiral galaxy Sc","mag":14.34,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":545927758.8895473,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":182.32295833333333,"dec_deg":44.09016666666667,"epoch_ra_deg":182.663047,"epoch_dec_deg":43.940669,"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":"Canes Venatici","discovered":"1881","featured":false,"url":"https://spacecatalog.org/object/ngc-4137","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.02,"h_mag":12.25,"j_mag":12.7,"k_mag":11.72,"v_mag":14.34,"redshift":0.03722,"hubble_type":"Sc","wikidata_id":"Q1109219","redshift_cmb":0.03799603311384936,"discovered_by":"Édouard Stephan","ngc_type_code":"G","uncertainties":{"distance_ly":[26275880.957893018,26275880.957893018]},"major_axis_arcmin":0.79,"minor_axis_arcmin":0.52,"position_angle_deg":175,"surface_brightness":22.99,"radial_velocity_km_s":10951},"designations":[{"catalog":"2MASX","designation":"2MASX J12091745+4405242"},{"catalog":"LEDA","designation":"LEDA 38619"},{"catalog":"MCG","designation":"MCG +07-25-033"},{"catalog":"NGC","designation":"NGC 4137"},{"catalog":"PGC","designation":"PGC 38619"},{"catalog":"SDSS","designation":"SDSS J120917.50+440524.6"},{"catalog":"SDSS","designation":"SDSS J120917.51+440524.6"},{"catalog":"UGC","designation":"UGC 07135 NED02"},{"catalog":"UGC","designation":"UGC 7135"}],"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."}