{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.676","julian_year":2026.676,"time":"2026-09-04T22:24:25.177Z","years_from_j2000":26.676,"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-139357-b","name":"HD 139357 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":365.58868378269773,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":233.8173564,"dec_deg":53.9221505,"epoch_ra_deg":233.997773,"epoch_dec_deg":53.83222,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 139357","semi_major_axis_km":441164120.69429994,"periapsis_km":null,"mass_kg":3.7717633921783713e+28,"mass_msun":0.0189687,"constellation":"Draco","discovered":"2008","featured":false,"url":"https://spacecatalog.org/object/hd-139357-b","radius_km":77175.01000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 139357","host_v_mag":5.97272,"eccentricity":0.099,"uncertainties":{"mass_kg":[6.527650498545446e+27,8.382118232513734e+27],"distance_ly":[2.276571516462869,2.276571516462869],"eccentricity":[0.023,0.023],"host_mass_solar":[0.258,0.258],"inclination_deg":[54.379,32.492],"host_radius_solar":[0.75,0.75],"host_temperature_k":[70,70],"semi_major_axis_km":[14810189.1993,14062199.8458],"orbital_period_days":[9.83725,11.83794],"argument_of_periastron_deg":[10.943,11.347]},"host_mass_solar":2.69,"inclination_deg":103.235,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":11.47,"planets_in_system":1,"discovery_facility":"Thueringer Landessternwarte Tautenburg","host_spectral_type":"K4 III","host_temperature_k":4700,"orbital_period_days":1124.79139,"periastron_epoch_bjd":2452470.581,"equilibrium_temperature_k":446.97,"argument_of_periastron_deg":235.995},"designations":[{"catalog":"Exoplanet","designation":"HD 139357 b"},{"catalog":"Host star","designation":"HD 139357"}],"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."}