{"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":"2026-09-02T09:57:06.129Z","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-451-c","name":"Kepler-451 c","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1292.6620949323235,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":294.6359173,"dec_deg":46.0664076,"epoch_ra_deg":294.837867,"epoch_dec_deg":46.12686,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"2MASS J19383260+4603591","semi_major_axis_km":null,"periapsis_km":null,"mass_kg":3.0559806056083204e+27,"mass_msun":0.0015369,"constellation":"Cygnus","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/kepler-451-c","radius_km":86104.35,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"2MASS J19383260+4603591","host_v_mag":12.651,"eccentricity":0.29,"uncertainties":{"mass_kg":[2.657374439659409e+26,2.657374439659409e+26],"distance_ly":[20.83650019043415,20.83650019043415],"eccentricity":[0.07,0.07],"host_radius_solar":[0.001,0.001],"orbital_period_days":[90,90],"argument_of_periastron_deg":[14,14]},"host_mass_solar":0.48,"stars_in_system":2,"discovery_method":"Eclipse Timing Variations","host_radius_solar":0.203,"planets_in_system":3,"discovery_facility":"Multiple Observatories","host_temperature_k":29564,"orbital_period_days":1460,"periastron_epoch_bjd":2456211,"argument_of_periastron_deg":7},"designations":[{"catalog":"Exoplanet","designation":"Kepler-451 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":"2026-09-01T22:58:55.274Z","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."}