{"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":"2026-09-05T11:06:11.104Z","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":"pgc-1647456","name":"PGC 1647456","class":"barred_spiral_galaxy_sbb","category":"galaxy","object_type":"Barred spiral galaxy SBb","mag":15.995,"mag_band":"B","abs_mag":-19.03545548938432,"abs_mag_band":"B","distance_ly":330763038.6792811,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":177.820343,"dec_deg":21.313639,"epoch_ra_deg":178.167416,"epoch_dec_deg":21.164277,"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":"Leo","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-1647456","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.995,"h_mag":13.082,"j_mag":13.806,"k_mag":12.712,"redshift":0.02308,"hubble_type":"SBb","redshift_cmb":0.023269406024884,"uncertainties":{"distance_ly":[21874659.37305147,21878777.704511978],"stellar_mass_solar":[2802370554.556028,2802370554.556028]},"major_axis_arcmin":0.47344,"minor_axis_arcmin":0.311571,"morphology_source":"SIMBAD (2018MNRAS.473.4731K, quality D)","position_angle_deg":137,"stellar_mass_solar":6538864627.297399},"designations":[{"catalog":"2MASX","designation":"2MASX 11511688+2118491"},{"catalog":"PGC","designation":"PGC 1647456"},{"catalog":"WISExSCOS","designation":"WISExSCOS J115116.88+211849.2"}],"source":{"id":"glade_plus","name":"GLADE+ (Galaxy List for the Advanced Detector Era)","url":"https://cdsarc.cds.unistra.fr/viz-bin/cat/VII/291","license":"VizieR terms; cite Dalya+ 2022 (2022MNRAS.514.1403D)"},"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."}