{"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":"2026-09-05T01:11:50.198Z","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-8574-b","name":"HD 8574 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":146.20416250081826,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":21.3033807,"dec_deg":28.5660169,"epoch_ra_deg":21.676255,"epoch_dec_deg":28.705985,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 8574","semi_major_axis_km":113694381.732,"periapsis_km":null,"mass_kg":3.853212250242872e+27,"mass_msun":0.00193784,"constellation":"Pisces","discovered":"2002","featured":false,"url":"https://spacecatalog.org/object/hd-8574-b","radius_km":85466.54000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 8574","host_v_mag":7.12,"eccentricity":0.3,"uncertainties":{"mass_kg":[2.657387758788188e+26,2.657387758788188e+26],"distance_ly":[0.30528236954287186,0.3065869950537388],"eccentricity":[0.03,0.03],"host_mass_solar":[0.12,0.12],"host_radius_solar":[0.02,0.02],"host_temperature_k":[14,14],"semi_major_axis_km":[1495978.707,1495978.707],"orbital_period_days":[0.2,0.2],"argument_of_periastron_deg":[4.9,5.1]},"host_mass_solar":1.34,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.38,"planets_in_system":1,"discovery_facility":"Haute-Provence Observatory","host_spectral_type":"F8","host_temperature_k":6064,"orbital_period_days":227,"periastron_epoch_bjd":2453981,"transit_midpoint_bjd":2453548.1,"equilibrium_temperature_k":394.03,"argument_of_periastron_deg":18},"designations":[{"catalog":"Exoplanet","designation":"HD 8574 b"},{"catalog":"Host star","designation":"HD 8574"}],"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."}