{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.685","julian_year":2026.685,"time":"2026-09-08T08:01:51.734Z","years_from_j2000":26.685,"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-125390-b","name":"HD 125390 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":501.12948967044474,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":214.5387463,"dec_deg":38.9669132,"epoch_ra_deg":214.815881,"epoch_dec_deg":38.842577,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 125390","semi_major_axis_km":522994155.9672,"periapsis_km":null,"mass_kg":5.163658161179377e+28,"mass_msun":0.0259688,"constellation":"Boötes","discovered":"2019","featured":false,"url":"https://spacecatalog.org/object/hd-125390-b","radius_km":75899.39,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 125390","host_v_mag":8.21,"eccentricity":0.597,"uncertainties":{"mass_kg":[5.9411299971788144e+26,7.835458347819632e+27],"distance_ly":[2.7853754657009886,2.7853754657009886],"eccentricity":[0.017,0.02],"host_mass_solar":[0.105,0.105],"inclination_deg":[19.71,25.699],"host_temperature_k":[29,29],"semi_major_axis_km":[10322253.0783,9873459.4662],"orbital_period_days":[5.44185,4.66922],"argument_of_periastron_deg":[1.439,1.598]},"host_mass_solar":1.82,"inclination_deg":84.685,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":6.47,"planets_in_system":1,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G7 III","host_temperature_k":4882,"orbital_period_days":1757.39151,"periastron_epoch_bjd":2454155.003,"equilibrium_temperature_k":320.26,"argument_of_periastron_deg":342.126},"designations":[{"catalog":"Exoplanet","designation":"HD 125390 b"},{"catalog":"Host star","designation":"HD 125390"}],"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."}