{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T22:44:00.907Z","years_from_j2000":26.687,"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":"hats-53-b","name":"HATS-53 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1910.5262137513678,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":176.628323,"dec_deg":-33.8600764,"epoch_ra_deg":176.965449,"epoch_dec_deg":-34.009316,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HATS-53","semi_major_axis_km":7110386.794371,"periapsis_km":null,"mass_kg":1.1293897974849796e+27,"mass_msun":0.000567986,"constellation":"Hydra","discovered":"2017","featured":false,"url":"https://spacecatalog.org/object/hats-53-b","radius_km":95799.44468600002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HATS-53","host_v_mag":13.944,"uncertainties":{"mass_kg":[1.6893393609439193e+26,1.6893393609439193e+26],"radius_km":[4003.5588824000006,4003.5588824000006],"distance_ly":[26.956824618288845,27.726553669700355],"host_mass_solar":[0.04,0.04],"inclination_deg":[0.55,0.55],"host_radius_solar":[0.024,0.031],"host_temperature_k":[94,94],"semi_major_axis_km":[98734.59466199999,98734.59466199999],"orbital_period_days":[0.0000038,0.0000038]},"host_mass_solar":0.964,"inclination_deg":88.78,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.101,"planets_in_system":1,"discovery_facility":"HATSouth","host_temperature_k":5644,"orbital_period_days":3.8537768,"transit_midpoint_bjd":2457236.75653,"eccentricity_upper_limit":0.33,"equilibrium_temperature_k":1312},"designations":[{"catalog":"Exoplanet","designation":"HATS-53 b"},{"catalog":"Host star","designation":"HATS-53"}],"source":{"id":"exoplanet_archive","name":"NASA Exoplanet Archive (Planetary Systems Composite Parameters)","url":"https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars","license":"Public domain (NASA)"},"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."}