{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.690","julian_year":2026.69,"time":"2026-09-09T20:13:45.759Z","years_from_j2000":26.69,"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-38594-c","name":"HIP 38594 c","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":58.01865340652061,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":118.5439118,"dec_deg":-25.3023073,"epoch_ra_deg":118.825565,"epoch_dec_deg":-25.372074,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 38594","semi_major_axis_km":569219898.0135,"periapsis_km":null,"mass_kg":2.8905292480110275e+26,"mass_msun":0.000145369,"constellation":"Puppis","discovered":"2020","featured":false,"url":"https://spacecatalog.org/object/hip-38594-c","radius_km":50642.11400000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 38594","host_v_mag":9.75,"eccentricity":0.16,"uncertainties":{"mass_kg":[4.419404222165621e+25,4.419404222165621e+25],"distance_ly":[0.030984855883090624,0.030984855883090624],"eccentricity":[0.1,0.1],"host_mass_solar":[0.02,0.02],"host_radius_solar":[0.018531,0.018531],"host_temperature_k":[97.3,168.9],"semi_major_axis_km":[25730833.760399997,25730833.760399997],"orbital_period_days":[229.001,229.001],"argument_of_periastron_deg":[68,68]},"host_mass_solar":0.61,"stars_in_system":2,"discovery_method":"Radial Velocity","host_radius_solar":0.626646,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_spectral_type":"M0","host_temperature_k":4086.3,"orbital_period_days":3477.768,"periastron_epoch_bjd":2451246.7,"equilibrium_temperature_k":79.96,"argument_of_periastron_deg":196},"designations":[{"catalog":"Exoplanet","designation":"HIP 38594 c"}],"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":"2026-09-09T11:17:28.634Z","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."}