{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.682","julian_year":2026.682,"time":"2026-09-07T01:26:54.639Z","years_from_j2000":26.682,"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":"k2-223-c","name":"K2-223 c","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":647.7596124005612,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":185.306183,"dec_deg":-10.2820915,"epoch_ra_deg":185.65261,"epoch_dec_deg":-10.431198,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-223","semi_major_axis_km":8212923.101429999,"periapsis_km":null,"mass_kg":1.7080400101883345e+25,"mass_msun":0.00000858998,"constellation":"Virgo","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/k2-223-c","radius_km":9567.150000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"K2-223","host_v_mag":11.443,"uncertainties":{"radius_km":[637.8100000000001,637.8100000000001],"distance_ly":[8.163694134250088,8.372434215988804],"host_mass_solar":[0.02,0.02],"inclination_deg":[3,4],"host_radius_solar":[0.06,0.06],"host_temperature_k":[50,50],"semi_major_axis_km":[44879.361209999995,44879.361209999995],"orbital_period_days":[0.00014,0.00014]},"host_mass_solar":1.06,"inclination_deg":89.6,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1,"planets_in_system":2,"discovery_facility":"K2","host_temperature_k":5859,"orbital_period_days":4.562546,"transit_midpoint_bjd":2457628.61208,"equilibrium_temperature_k":1091},"designations":[{"catalog":"Exoplanet","designation":"K2-223 c"}],"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."}