{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T10:43:22.241Z","years_from_j2000":26.672,"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-2315899","name":"PGC 2315899","class":"spiral_galaxy","category":"galaxy","object_type":"Spiral galaxy","mag":16.54,"mag_band":"B","abs_mag":-18.031537577274243,"abs_mag_band":"B","distance_ly":267752411.30806994,"distance_method":"luminosity distance from a photometric redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":239.439392,"dec_deg":48.36731,"epoch_ra_deg":239.639977,"epoch_dec_deg":48.289548,"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":"Hercules","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/pgc-2315899","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":16.54,"h_mag":14.224,"j_mag":14.829,"k_mag":13.915,"redshift":0.0189873694937,"hubble_type":"4.12","redshift_cmb":0.0188975890046365,"uncertainties":{"distance_ly":[55686729.38886541,55981025.840658955],"stellar_mass_solar":[934149200.3556244,934149200.3556244]},"major_axis_arcmin":0.524763,"minor_axis_arcmin":0.263903,"morphology_source":"SIMBAD (2024ApJ...970...83B, quality C)","position_angle_deg":70,"stellar_mass_solar":1868298400.7112489},"designations":[{"catalog":"2MASX","designation":"2MASX 15574545+4822023"},{"catalog":"PGC","designation":"PGC 2315899"},{"catalog":"WISExSCOS","designation":"WISExSCOS J155745.38+482201.6"}],"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."}