{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.686","julian_year":2026.686,"time":"2026-09-08T13:35:43.562Z","years_from_j2000":26.686,"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-91258-b","name":"HIP 91258 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":149.65554928981686,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":279.2211173,"dec_deg":61.7015065,"epoch_ra_deg":279.290364,"epoch_dec_deg":61.723284,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 91258","semi_major_axis_km":8975872.241999999,"periapsis_km":null,"mass_kg":2.0689661836279463e+27,"mass_msun":0.00104051,"constellation":"Draco","discovered":"2013","featured":false,"url":"https://spacecatalog.org/object/hip-91258-b","radius_km":87379.97,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 91258","host_v_mag":8.65,"eccentricity":0.02,"uncertainties":{"mass_kg":[3.9860816381822815e+26,3.9860816381822815e+26],"distance_ly":[0.21526320929305068,0.21558936567076742],"eccentricity":[0.01,0.01],"host_mass_solar":[0.28,0.28],"host_radius_solar":[0.03,0.03],"host_temperature_k":[70,70],"orbital_period_days":[0.0015,0.0015],"argument_of_periastron_deg":[64,64]},"host_mass_solar":0.97,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.89,"planets_in_system":1,"discovery_facility":"Haute-Provence Observatory","host_spectral_type":"G5 V","host_temperature_k":5519,"orbital_period_days":5.0505,"equilibrium_temperature_k":1024.97,"argument_of_periastron_deg":276},"designations":[{"catalog":"Exoplanet","designation":"HIP 91258 b"},{"catalog":"Host star","designation":"HIP 91258"}],"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."}