{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.654","julian_year":2026.654,"time":"2026-08-27T18:01:35.549Z","years_from_j2000":26.654,"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":"hip-98599-b","name":"HIP 98599 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":247.69228561667103,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":300.4090608,"dec_deg":-22.1110649,"epoch_ra_deg":300.805642,"epoch_dec_deg":-22.036965,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 98599","semi_major_axis_km":592407567.972,"periapsis_km":null,"mass_kg":1.3002153508333538e+28,"mass_msun":0.00653897,"constellation":"Sagittarius","discovered":"2026","featured":false,"url":"https://spacecatalog.org/object/hip-98599-b","radius_km":81001.87,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 98599","host_v_mag":8.11,"eccentricity":0.169,"uncertainties":{"mass_kg":[4.1758741194647855e+26,1.8981245997567207e+26],"distance_ly":[0.9680321290632945,0.9755337257507795],"eccentricity":[0.055,0.002],"host_mass_solar":[0.04,0.04],"inclination_deg":[6.2,6.9],"host_radius_solar":[0.051753,0.051785],"host_temperature_k":[300,300],"semi_major_axis_km":[1495978.707,10471850.949000001],"orbital_period_days":[16,40],"argument_of_periastron_deg":[16,3]},"host_mass_solar":1.19,"inclination_deg":29.7,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.39484,"planets_in_system":1,"discovery_facility":"Multiple Facilities","host_spectral_type":"F7 V","host_temperature_k":5978,"orbital_period_days":2656,"equilibrium_temperature_k":171.08,"argument_of_periastron_deg":275},"designations":[{"catalog":"Exoplanet","designation":"HIP 98599 b"},{"catalog":"Host star","designation":"HIP 98599"}],"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":"2026-08-27T16:03:54.983Z","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."}