{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.686","julian_year":2026.686,"time":"2026-09-08T13:36:15.402Z","years_from_j2000":26.686,"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-168009-b","name":"HD 168009 b","class":"neptune_like_planet","category":"exoplanet","object_type":"Neptune-like planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":76.00487301208815,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":273.8847918,"dec_deg":45.2088229,"epoch_ra_deg":274.078577,"epoch_dec_deg":45.216902,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 168009","semi_major_axis_km":17832066.18744,"periapsis_km":null,"mass_kg":5.694373799270162e+25,"mass_msun":0.0000286378,"constellation":"Lyra","discovered":"2021","featured":false,"url":"https://spacecatalog.org/object/hd-168009-b","radius_km":19453.205,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 168009","host_v_mag":6.295,"eccentricity":0.12,"uncertainties":{"mass_kg":[7.023061043585754e+24,7.212873499380909e+24],"distance_ly":[0.03848645257057572,0.03848645257057572],"eccentricity":[0.082,0.11],"host_mass_solar":[0.043823,0.043823],"host_radius_solar":[0.028281,0.028281],"host_temperature_k":[94.42,94.42],"semi_major_axis_km":[269276.16725999996,254316.38018999997],"orbital_period_days":[0.0037,0.0035],"argument_of_periastron_deg":[63.0254,45.8366]},"host_mass_solar":0.986073,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.209505,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"G2V","host_temperature_k":5778.33,"orbital_period_days":15.1479,"transit_midpoint_bjd":2455201.56,"equilibrium_temperature_k":887.57,"argument_of_periastron_deg":13.178},"designations":[{"catalog":"Exoplanet","designation":"HD 168009 b"},{"catalog":"Host star","designation":"HD 168009"}],"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."}