{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.670","julian_year":2026.67,"time":"2026-09-02T20:02:51.549Z","years_from_j2000":26.67,"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-438-b","name":"Kepler-438 b","class":"terrestrial_planet","category":"exoplanet","object_type":"Terrestrial planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":639.0801728939641,"distance_method":"NASA Exoplanet Archive sy_dist (Gaia DR2, 2018A&A...616A...1G)","ra_deg":281.6457236,"dec_deg":41.9510686,"epoch_ra_deg":281.857716,"epoch_dec_deg":41.979259,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-438","semi_major_axis_km":24833246.536199998,"periapsis_km":null,"mass_kg":8.719365086975414e+24,"mass_msun":0.00000438509,"constellation":"Lyra","discovered":"2015","featured":false,"url":"https://spacecatalog.org/object/kepler-438-b","radius_km":7143.472000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-438","host_v_mag":15.104,"uncertainties":{"radius_km":[1084.277,1020.4960000000001],"distance_ly":[15.423756825148736,15.423756825148736],"host_mass_solar":[0.061,0.041],"inclination_deg":[0.32,0.14],"host_radius_solar":[0.061,0.038],"host_temperature_k":[112,112],"semi_major_axis_km":[6283110.569399999,7629491.405699999],"orbital_period_days":[0.00029,0.00025]},"host_mass_solar":0.544,"inclination_deg":89.86,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.52,"planets_in_system":1,"discovery_facility":"Kepler","host_temperature_k":3748,"orbital_period_days":35.23319,"transit_midpoint_bjd":2455673.0307,"eccentricity_lower_limit":0.03,"equilibrium_temperature_k":288},"designations":[{"catalog":"Exoplanet","designation":"Kepler-438 b"},{"catalog":"Host star","designation":"Kepler-438"}],"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."}