{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.676","julian_year":2026.676,"time":"2026-09-04T18:40:28.910Z","years_from_j2000":26.676,"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-450-c","name":"Kepler-450 c","class":"neptune_like_planet","category":"exoplanet","object_type":"Neptune-like planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1487.2143742403612,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":295.4865821,"dec_deg":51.0135237,"epoch_ra_deg":295.662658,"epoch_dec_deg":51.076004,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-450","semi_major_axis_km":19972811.717156995,"periapsis_km":null,"mass_kg":7.465209834739224e+25,"mass_msun":0.0000375436,"constellation":"Cygnus","discovered":"2015","featured":false,"url":"https://spacecatalog.org/object/kepler-450-c","radius_km":16710.622000000003,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-450","host_v_mag":11.991,"eccentricity":0.02,"uncertainties":{"mass_kg":[1.5527636456257586e+25,1.9110937176932413e+25],"radius_km":[892.9340000000001,892.9340000000001],"distance_ly":[16.54917460534756,16.924254439721818],"eccentricity":[0.02,0.17],"host_mass_solar":[0.142064,0.197747],"host_radius_solar":[0.106909,0.080191],"host_temperature_k":[187.39,130.15],"semi_major_axis_km":[110702.42431799999,110702.42431799999],"orbital_period_days":[0.000085,0.000085]},"host_mass_solar":1.19,"inclination_deg":88.73,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.64162,"planets_in_system":3,"discovery_facility":"Kepler","host_temperature_k":6197.21,"orbital_period_days":15.413135,"transit_midpoint_bjd":2454969.94071,"equilibrium_temperature_k":944},"designations":[{"catalog":"Exoplanet","designation":"Kepler-450 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":"2026-09-02T19:50:56.720Z","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."}