{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.683","julian_year":2026.683,"time":"2026-09-07T13:11:34.243Z","years_from_j2000":26.683,"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":"hat-p-57-b","name":"HAT-P-57 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":912.7812386780781,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":274.743418,"dec_deg":10.5971968,"epoch_ra_deg":275.059741,"epoch_dec_deg":10.607684,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HAT-P-57","semi_major_axis_km":6073673.550419999,"periapsis_km":null,"mass_kg":2.676369099922389e+27,"mass_msun":0.00134598,"constellation":"Ophiuchus","discovered":"2015","featured":false,"url":"https://spacecatalog.org/object/hat-p-57-b","radius_km":124396.293846,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HAT-P-57","host_v_mag":10.639,"eccentricity":0,"uncertainties":{"mass_kg":[2.885163852398604e+27,2.885163852398604e+27],"radius_km":[25737.164244,25737.164244],"distance_ly":[10.358726556283772,10.596820712016994],"host_mass_solar":[1.74,1.74],"inclination_deg":[0.85,0.85],"host_radius_solar":[0.39,0.39],"host_temperature_k":[124,124],"semi_major_axis_km":[164557.65777,164557.65777],"orbital_period_days":[0.000003,0.000003]},"host_mass_solar":2.77,"inclination_deg":88.26,"stars_in_system":3,"discovery_method":"Transit","host_radius_solar":1.85,"planets_in_system":1,"discovery_facility":"HATNet","host_spectral_type":"A8 V","host_temperature_k":6330,"orbital_period_days":2.4653,"transit_midpoint_bjd":2457598.49926,"equilibrium_temperature_k":2200},"designations":[{"catalog":"Exoplanet","designation":"HAT-P-57 b"},{"catalog":"Host star","designation":"HAT-P-57"}],"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."}