{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.664","julian_year":2026.664,"time":"2026-08-31T13:28:06.711Z","years_from_j2000":26.664,"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-1388-e","name":"Kepler-1388 e","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":1480.081334259696,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":283.3360156,"dec_deg":47.1744499,"epoch_ra_deg":283.522469,"epoch_dec_deg":47.2069,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-1388","semi_major_axis_km":27840163.737269998,"periapsis_km":null,"mass_kg":3.953575128477893e+25,"mass_msun":0.0000198831,"constellation":"Lyra","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/kepler-1388-e","radius_km":15690.126,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-1388","host_v_mag":16.43,"eccentricity":0,"uncertainties":{"radius_km":[956.715,892.9340000000001],"distance_ly":[24.404650962655325,24.404650962655325],"host_mass_solar":[0.03,0.021],"host_radius_solar":[0.028,0.02],"host_temperature_k":[51.9,48.16],"orbital_period_days":[0.0007269,0.0007269]},"host_mass_solar":0.63,"inclination_deg":89.69,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.61,"planets_in_system":4,"discovery_facility":"Kepler","host_temperature_k":4098,"orbital_period_days":37.6327084,"transit_midpoint_bjd":2454991.8322,"equilibrium_temperature_k":299},"designations":[{"catalog":"Exoplanet","designation":"Kepler-1388 e"}],"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":"2026-08-30T09:56:50.739Z","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."}