{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T19:23:01.592Z","years_from_j2000":26.678,"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":"k2-111-c","name":"K2-111 c","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":653.5978115616908,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":59.8903081,"dec_deg":21.2985263,"epoch_ra_deg":60.284664,"epoch_dec_deg":21.375083,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-111","semi_major_axis_km":17300993.746455,"periapsis_km":null,"mass_kg":6.629106333248431e+25,"mass_msun":0.0000333387,"constellation":"Taurus","discovered":"2020","featured":false,"url":"https://spacecatalog.org/object/k2-111-c","radius_km":21302.854,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"K2-111","host_v_mag":11.13,"eccentricity":0.069,"uncertainties":{"mass_kg":[5.972167867791379e+24,6.569384654570517e+24],"distance_ly":[8.773606560580397,9.011700716313621],"eccentricity":[0.049,0.072],"host_mass_solar":[0.02,0.02],"host_radius_solar":[0.02,0.02],"host_temperature_k":[60,60],"semi_major_axis_km":[137630.04104399998,137630.04104399998],"orbital_period_days":[0.0061,0.0062],"argument_of_periastron_deg":[150.1,96.3]},"host_mass_solar":0.84,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.25,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_spectral_type":"G2","host_temperature_k":5775,"orbital_period_days":15.6748,"transit_midpoint_bjd":2458119.62,"equilibrium_temperature_k":923,"argument_of_periastron_deg":-79.6},"designations":[{"catalog":"Exoplanet","designation":"K2-111 c"},{"catalog":"Host star","designation":"K2-111"}],"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."}