{"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":"2026-09-07T18:52:11.507Z","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":"wasp-120-b","name":"WASP-120 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1243.2233111980195,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":62.6160813,"dec_deg":-45.8982434,"epoch_ra_deg":62.824423,"epoch_dec_deg":-45.827635,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"WASP-120","semi_major_axis_km":7689330.553979999,"periapsis_km":null,"mass_kg":9.20595045008765e+27,"mass_msun":0.00462981,"constellation":"Horologium","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/wasp-120-b","radius_km":99373.879706577,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"WASP-120","host_v_mag":10.96,"eccentricity":0.057,"uncertainties":{"mass_kg":[3.9860816381822815e+26,3.9860816381822815e+26],"radius_km":[5719.3600097260005,5719.3600097260005],"distance_ly":[10.36198812006094,10.534851000250812],"eccentricity":[0.018,0.022],"host_mass_solar":[0.057,0.057],"inclination_deg":[0.35,0.35],"host_radius_solar":[0.07301,0.07301],"host_temperature_k":[120,120],"semi_major_axis_km":[104718.50949,104718.50949],"orbital_period_days":[7.8e-7,7.8e-7],"argument_of_periastron_deg":[28,48]},"host_mass_solar":1.393,"inclination_deg":84.54,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.68443,"planets_in_system":1,"discovery_facility":"SuperWASP","host_spectral_type":"F5","host_temperature_k":6450,"orbital_period_days":3.61126721,"transit_midpoint_bjd":2456779.4347,"equilibrium_temperature_k":1749,"argument_of_periastron_deg":333},"designations":[{"catalog":"Exoplanet","designation":"WASP-120 b"},{"catalog":"Host star","designation":"WASP-120"}],"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."}