{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.684","julian_year":2026.684,"time":"2026-09-07T23:09:01.777Z","years_from_j2000":26.684,"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":"eso-553-023","name":"ESO 553-023","class":"galaxy","category":"galaxy","object_type":"Galaxy","mag":14.957,"mag_band":"B","abs_mag":-22.070878414073576,"abs_mag_band":"B","distance_ly":829853744.594573,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":78.090729,"dec_deg":-19.162981,"epoch_ra_deg":78.384322,"epoch_dec_deg":-19.130228,"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":"Lepus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/eso-553-023","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":14.957,"h_mag":11.968,"j_mag":12.716,"k_mag":11.655,"redshift":0.05693,"redshift_cmb":0.056982,"uncertainties":{"distance_ly":[41731788.35636955,41764430.34909892],"stellar_mass_solar":[37428063645.96606,37428063645.96606]},"stellar_mass_solar":84213143203.42363},"designations":[{"catalog":"2MASX","designation":"2MASX 05122177-1909467"},{"catalog":"WISExSCOS","designation":"WISExSCOS J051221.76-190946.8"}],"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."}