{"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":"2026-09-02T11:36:42.246Z","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-243-b","name":"Kepler-243 b","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":2263.068642425396,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":285.1104819,"dec_deg":42.0339619,"epoch_ra_deg":285.32384,"epoch_dec_deg":42.070971,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-243","semi_major_axis_km":9275067.983399998,"periapsis_km":null,"mass_kg":3.923714289138936e+25,"mass_msun":0.0000197329,"constellation":"Lyra","discovered":"2014","featured":false,"url":"https://spacecatalog.org/object/kepler-243-b","radius_km":15626.345000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-243","host_v_mag":15.159,"eccentricity":0,"uncertainties":{"radius_km":[7398.596,7398.596],"distance_ly":[31.089225923959983,31.950278761132182],"host_mass_solar":[0.023,0.018],"host_radius_solar":[0.398,0.398],"host_temperature_k":[200,200],"orbital_period_days":[0.000011,0.000011]},"host_mass_solar":0.904,"inclination_deg":88.81,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.842,"planets_in_system":2,"discovery_facility":"Kepler","host_temperature_k":5228,"orbital_period_days":5.715442,"transit_midpoint_bjd":2455007.87832,"equilibrium_temperature_k":850},"designations":[{"catalog":"Exoplanet","designation":"Kepler-243 b"},{"catalog":"Host star","designation":"Kepler-243"}],"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."}