{"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":"2026-09-02T15:36:31.292Z","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-222-d","name":"Kepler-222 d","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":2475.050718558616,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":287.9060885,"dec_deg":46.9377479,"epoch_ra_deg":288.09711,"epoch_dec_deg":46.981751,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-222","semi_major_axis_km":26927616.725999996,"periapsis_km":null,"mass_kg":7.88326158548462e+25,"mass_msun":0.0000396461,"constellation":"Lyra","discovered":"2014","featured":false,"url":"https://spacecatalog.org/object/kepler-222-d","radius_km":23535.189000000002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-222","host_v_mag":15.407,"eccentricity":0,"uncertainties":{"radius_km":[10396.303,10396.303],"distance_ly":[47.29593633270496,49.14198143058173],"host_mass_solar":[0.011,0.019],"host_radius_solar":[0.38,0.38],"host_temperature_k":[200,200],"orbital_period_days":[0.000069,0.000069]},"host_mass_solar":0.933,"inclination_deg":89.46,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.869,"planets_in_system":3,"discovery_facility":"Kepler","host_temperature_k":5433,"orbital_period_days":28.081912,"transit_midpoint_bjd":2455027.91404,"equilibrium_temperature_k":522},"designations":[{"catalog":"Exoplanet","designation":"Kepler-222 d"}],"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."}