{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T16:41:02.645Z","years_from_j2000":26.681,"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":"kelt-20-b","name":"KELT-20 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":444.96209986384434,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":294.6614126,"dec_deg":31.2192001,"epoch_ra_deg":294.922655,"epoch_dec_deg":31.279833,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"KELT-20","semi_major_axis_km":8108204.591939999,"periapsis_km":null,"mass_kg":6.419489571586893e+27,"mass_msun":0.00322845,"constellation":"Cygnus","discovered":"2017","featured":false,"url":"https://spacecatalog.org/object/kelt-20-b","radius_km":124467.78596890002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"KELT-20","host_v_mag":7.59,"eccentricity":0,"uncertainties":{"radius_km":[5290.4170946,4932.956480100001],"distance_ly":[2.6320819681741194,2.661436042168626],"host_mass_solar":[0.19,0.14],"inclination_deg":[0.27,0.28],"host_radius_solar":[0.064,0.057],"host_temperature_k":[260,250],"semi_major_axis_km":[314155.52846999996,209437.01898],"orbital_period_days":[0.0000019,0.0000019]},"host_mass_solar":1.76,"inclination_deg":86.12,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.565,"planets_in_system":1,"discovery_facility":"KELT-North","host_spectral_type":"A2 V","host_temperature_k":8720,"orbital_period_days":3.4741085,"transit_midpoint_bjd":2457503.120049,"equilibrium_temperature_k":2262},"designations":[{"catalog":"Exoplanet","designation":"KELT-20 b"},{"catalog":"Host star","designation":"KELT-20"}],"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."}