{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.685","julian_year":2026.685,"time":"2026-09-08T08:57:25.006Z","years_from_j2000":26.685,"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-154345-b","name":"HD 154345 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":59.63443210172936,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":255.6524619,"dec_deg":47.0855544,"epoch_ra_deg":255.841522,"epoch_dec_deg":47.046483,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 154345","semi_major_axis_km":622027946.3706,"periapsis_km":null,"mass_kg":2.2511757752995264e+27,"mass_msun":0.00113215,"constellation":"Hercules","discovered":"2006","featured":false,"url":"https://spacecatalog.org/object/hd-154345-b","radius_km":87379.97,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 154345","host_v_mag":6.76,"eccentricity":0.058,"uncertainties":{"mass_kg":[1.1198935136773001e+26,1.803218369470276e+26],"distance_ly":[0.023157102817888783,0.023483259195605524],"eccentricity":[0.019,0.019],"host_mass_solar":[0.04,0.04],"inclination_deg":[20,20],"host_radius_solar":[0.01,0.01],"host_temperature_k":[14,14],"semi_major_axis_km":[10023057.3369,9873459.4662],"orbital_period_days":[28,29],"argument_of_periastron_deg":[21,18]},"host_mass_solar":0.89,"inclination_deg":88,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.85,"planets_in_system":1,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G8","host_temperature_k":5468,"orbital_period_days":3280,"periastron_epoch_bjd":2458230,"transit_midpoint_bjd":2456384,"equilibrium_temperature_k":119.21,"argument_of_periastron_deg":309},"designations":[{"catalog":"Exoplanet","designation":"HD 154345 b"},{"catalog":"Host star","designation":"HD 154345"}],"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."}