{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.674","julian_year":2026.674,"time":"2026-09-04T00:44:05.309Z","years_from_j2000":26.674,"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-220197-b","name":"HD 220197 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":210.0805844511316,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":350.4946927,"dec_deg":16.6323305,"epoch_ra_deg":350.830809,"epoch_dec_deg":16.779479,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 220197","semi_major_axis_km":408252589.1403,"periapsis_km":null,"mass_kg":3.7962682268402685e+26,"mass_msun":0.00019092,"constellation":"Pegasus","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/hd-220197-b","radius_km":59443.89200000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 220197","host_v_mag":8.92,"eccentricity":0.187,"uncertainties":{"mass_kg":[7.592536453680536e+25,1.328693879394094e+26],"distance_ly":[0.6301341217487483,0.6340479982813492],"eccentricity":[0.132,0.279],"host_mass_solar":[0.02,0.02],"host_radius_solar":[0.02,0.02],"host_temperature_k":[15,15],"semi_major_axis_km":[12715819.0095,25132442.277599998],"orbital_period_days":[80,162],"argument_of_periastron_deg":[80.914,54.933]},"host_mass_solar":0.91,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.98,"planets_in_system":1,"discovery_facility":"Roque de los Muchachos Observatory","host_spectral_type":"G5","host_temperature_k":5683,"orbital_period_days":1728,"periastron_epoch_bjd":2456636.3,"equilibrium_temperature_k":164.22,"argument_of_periastron_deg":159.011},"designations":[{"catalog":"Exoplanet","designation":"HD 220197 b"},{"catalog":"Host star","designation":"HD 220197"}],"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."}