{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.680","julian_year":2026.68,"time":"2026-09-06T10:02:10.842Z","years_from_j2000":26.68,"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":"hd-203387-b","name":"HD 203387 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":201.39406164340159,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":320.561782,"dec_deg":-16.8345229,"epoch_ra_deg":320.935048,"epoch_dec_deg":-16.72016,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 203387","semi_major_axis_km":264937829.00969997,"periapsis_km":null,"mass_kg":6.605473607153389e+27,"mass_msun":0.00332199,"constellation":"Capricornus","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/hd-203387-b","radius_km":83553.11,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 203387","host_v_mag":4.28,"eccentricity":0.732,"uncertainties":{"mass_kg":[1.0079041624887351e+27,1.1179953892387919e+27],"distance_ly":[3.765638458928661,3.765638458928661],"eccentricity":[0.049,0.049],"host_mass_solar":[0.271,0.271],"host_temperature_k":[23.92,23.92],"semi_major_axis_km":[9275067.983399998,8377480.759199999],"orbital_period_days":[8.15674,7.53525],"argument_of_periastron_deg":[3.529,2.964]},"host_mass_solar":2.817,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":10.5852,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_temperature_k":5174.32,"orbital_period_days":512.5352,"periastron_epoch_bjd":2453040.709,"equilibrium_temperature_k":610,"argument_of_periastron_deg":350.068},"designations":[{"catalog":"Exoplanet","designation":"HD 203387 b"},{"catalog":"Host star","designation":"HD 203387"}],"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."}