{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.675","julian_year":2026.675,"time":"2026-09-04T11:55:14.137Z","years_from_j2000":26.675,"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":"kepler-91-b","name":"Kepler-91 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":4222.714006660905,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":285.6729033,"dec_deg":44.1167513,"epoch_ra_deg":285.876792,"epoch_dec_deg":44.155194,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-91","semi_major_axis_km":10935604.34817,"periapsis_km":null,"mass_kg":1.5374886318703086e+27,"mass_msun":0.000773225,"constellation":"Lyra","discovered":"2013","featured":false,"url":"https://spacecatalog.org/object/kepler-91-b","radius_km":97729.7320043,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-91","host_v_mag":12.712,"eccentricity":0.0519,"uncertainties":{"mass_kg":[3.226827992814228e+26,3.416641404156241e+26],"radius_km":[4289.527374,4932.956480100001],"distance_ly":[132.85980046291542,132.85980046291542],"eccentricity":[0.0088,0.0095],"host_mass_solar":[0.1,0.1],"inclination_deg":[0.57,0.67],"host_radius_solar":[0.16,0.16],"host_temperature_k":[75,75],"semi_major_axis_km":[463753.39916999993,508632.76037999993],"orbital_period_days":[0.00008,0.00008],"argument_of_periastron_deg":[7.1,8.7]},"host_mass_solar":1.31,"inclination_deg":69.68,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":6.3,"planets_in_system":1,"discovery_facility":"Kepler","host_spectral_type":"K3","host_temperature_k":4550,"orbital_period_days":6.24658,"transit_midpoint_bjd":2454969.3958,"equilibrium_temperature_k":2040,"argument_of_periastron_deg":-57.2},"designations":[{"catalog":"Exoplanet","designation":"Kepler-91 b"},{"catalog":"Host star","designation":"Kepler-91"}],"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."}