{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T11:51:59.257Z","years_from_j2000":26.669,"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":"ic-4952","name":"IC 4952","class":"lenticular_galaxy_s0_a","category":"galaxy","object_type":"Lenticular galaxy S0-a","mag":14,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":196831131.5117657,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":302.15687499999996,"dec_deg":-55.45366666666667,"epoch_ra_deg":302.685679,"epoch_dec_deg":-55.375474,"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":"Telescopium","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/ic-4952","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":14,"h_mag":10.2,"j_mag":10.96,"k_mag":9.96,"redshift":0.01431,"hubble_type":"S0-a","wikidata_id":"Q3680827","redshift_cmb":0.013943432076032547,"ngc_type_code":"G","uncertainties":{"distance_ly":[16199555.050624574,16199555.050624574]},"major_axis_arcmin":0.93,"minor_axis_arcmin":0.21,"position_angle_deg":8,"surface_brightness":22.43,"radial_velocity_km_s":4259},"designations":[{"catalog":"2MASX","designation":"2MASX J20083763-5527132"},{"catalog":"ESO","designation":"ESO 186-001"},{"catalog":"ESO","designation":"ESO 186-1"},{"catalog":"ESO-LV","designation":"ESO-LV 186-0010"},{"catalog":"IC","designation":"IC 4952"},{"catalog":"LEDA","designation":"LEDA 64163"},{"catalog":"PGC","designation":"PGC 64163"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","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."}