{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T21:57:02.706Z","years_from_j2000":26.687,"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-165131-b","name":"HD 165131 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":187.29953993675022,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":271.3444007,"dec_deg":-21.6737039,"epoch_ra_deg":271.748163,"epoch_dec_deg":-21.671985,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 165131","semi_major_axis_km":529576462.27799994,"periapsis_km":null,"mass_kg":3.5494930015450676e+28,"mass_msun":0.0178509,"constellation":"Sagittarius","discovered":"2023","featured":false,"url":"https://spacecatalog.org/object/hd-165131-b","radius_km":77175.01000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 165131","host_v_mag":8.42,"eccentricity":0.6708,"uncertainties":{"mass_kg":[1.8981245997567207e+27,2.657374439659409e+27],"distance_ly":[0.6836237676942942,0.6885161133600454],"eccentricity":[0.0019,0.0019],"host_mass_solar":[0.05,0.05],"inclination_deg":[8.5,12],"host_radius_solar":[0.052493,0.046688],"host_temperature_k":[100,100],"semi_major_axis_km":[8078285.0178,8078285.0178],"orbital_period_days":[1.3,1.3],"argument_of_periastron_deg":[0.29,0.29]},"host_mass_solar":1.06,"inclination_deg":70,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.06419,"planets_in_system":1,"discovery_facility":"Multiple Facilities","host_spectral_type":"G3/5 V","host_temperature_k":5870,"orbital_period_days":2342.6,"periastron_epoch_bjd":2455590.1,"equilibrium_temperature_k":155.2,"argument_of_periastron_deg":3.61},"designations":[{"catalog":"Exoplanet","designation":"HD 165131 b"},{"catalog":"Host star","designation":"HD 165131"}],"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."}