{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.674","julian_year":2026.674,"time":"2026-09-04T02:39:13.926Z","years_from_j2000":26.674,"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":"k2-233-c","name":"K2-233 c","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":220.17577665422027,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":230.4799011,"dec_deg":-20.2317975,"epoch_ra_deg":230.866176,"epoch_dec_deg":-20.328317,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-233","semi_major_axis_km":9933298.61448,"periapsis_km":null,"mass_kg":2.7471972191840344e+25,"mass_msun":0.0000138161,"constellation":"Libra","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/k2-233-c","radius_km":8112.943200000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"K2-233","host_v_mag":10.883,"eccentricity":0,"uncertainties":{"mass_kg":[1.0152685375245345e+25,1.0749902162024483e+25],"radius_km":[242.36780000000002,242.36780000000002],"distance_ly":[0.9050839481639631,0.9129117012291648],"host_mass_solar":[0.01,0.01],"inclination_deg":[0.35,0.29],"host_radius_solar":[0.01,0.01],"host_temperature_k":[66,66],"semi_major_axis_km":[194477.23190999997,194477.23190999997],"orbital_period_days":[0.00043,0.00044]},"host_mass_solar":0.79,"inclination_deg":89.57,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.71,"planets_in_system":3,"discovery_facility":"K2","host_spectral_type":"K3","host_temperature_k":4796,"orbital_period_days":7.06024,"periastron_epoch_bjd":2457586.862,"transit_midpoint_bjd":2457586.862,"equilibrium_temperature_k":794,"argument_of_periastron_deg":90},"designations":[{"catalog":"Exoplanet","designation":"K2-233 c"},{"catalog":"Host star","designation":"K2-233"}],"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."}