{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.682","julian_year":2026.682,"time":"2026-09-07T04:47:32.518Z","years_from_j2000":26.682,"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-3157","name":"IC 3157","class":"lenticular_galaxy_s0","category":"galaxy","object_type":"Lenticular galaxy S0","mag":15.09,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":890229888.2909681,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":184.94966666666667,"dec_deg":12.421944444444444,"epoch_ra_deg":185.291487,"epoch_dec_deg":12.272763,"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":null,"featured":false,"url":"https://spacecatalog.org/object/ic-3157","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.09,"h_mag":11.36,"j_mag":12.11,"k_mag":11.04,"redshift":0.05978,"hubble_type":"S0","wikidata_id":"Q3687499","redshift_cmb":0.06095793189220999,"ngc_type_code":"G","uncertainties":{"distance_ly":[38726816.727309324,38726816.727309324]},"major_axis_arcmin":0.96,"minor_axis_arcmin":0.54,"position_angle_deg":109,"surface_brightness":23.73,"radial_velocity_km_s":17387},"designations":[{"catalog":"2MASX","designation":"2MASX J12194788+1225191"},{"catalog":"IC","designation":"IC 3157"},{"catalog":"LEDA","designation":"LEDA 39716"},{"catalog":"PGC","designation":"PGC 39716"},{"catalog":"SDSS","designation":"SDSS J121947.91+122518.9"},{"catalog":"SDSS","designation":"SDSS J121947.92+122519.0"}],"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."}