{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T06:36:30.771Z","years_from_j2000":26.669,"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-129-d","name":"Kepler-129 d","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1333.4740424760198,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":285.3111845,"dec_deg":47.8484775,"epoch_ra_deg":285.495214,"epoch_dec_deg":47.885954,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-129","semi_major_axis_km":598391482.8,"periapsis_km":null,"mass_kg":1.575443417798078e+28,"mass_msun":0.00792313,"constellation":"Draco","discovered":"2021","featured":false,"url":"https://spacecatalog.org/object/kepler-129-d","radius_km":80364.06,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-129","host_v_mag":11.809,"eccentricity":0.15,"uncertainties":{"mass_kg":[1.3286872198297045e+27,2.0879370597323925e+27],"distance_ly":[14.050816752037306,14.347619055759543],"eccentricity":[0.05,0.07],"host_mass_solar":[0.03,0.021],"host_radius_solar":[0.012,0.009],"host_temperature_k":[83,83],"semi_major_axis_km":[14959787.07,14959787.07],"orbital_period_days":[94,140],"argument_of_periastron_deg":[57,46]},"host_mass_solar":1.178,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.653,"planets_in_system":3,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G4 V","host_temperature_k":5770,"orbital_period_days":2646,"periastron_epoch_bjd":2458637,"equilibrium_temperature_k":178.86,"argument_of_periastron_deg":-170},"designations":[{"catalog":"Exoplanet","designation":"Kepler-129 d"},{"catalog":"Host star","designation":"Kepler-129"}],"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":"2026-09-01T22:58:55.274Z","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."}