{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.671","julian_year":2026.671,"time":"2026-09-03T03:50:38.635Z","years_from_j2000":26.671,"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":"k2-417-b","name":"K2-417 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":306.7252853578907,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":350.1417675,"dec_deg":-10.0365901,"epoch_ra_deg":350.490618,"epoch_dec_deg":-9.889623,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-417","semi_major_axis_km":9424665.8541,"periapsis_km":null,"mass_kg":4.175874119464785e+27,"mass_msun":0.00210011,"constellation":"Aquarius","discovered":"2023","featured":false,"url":"https://spacecatalog.org/object/k2-417-b","radius_km":21111.511000000002,"radius_kind":null,"data_quality":"The published mass and radius imply a density no material has. One of the two is likely an upper limit rather than a measurement.","description":null,"properties":{"host_star":"K2-417","host_v_mag":13.909,"uncertainties":{"radius_km":[765.3720000000001,892.9340000000001],"distance_ly":[0.9794476022833806,0.9859707298377154],"host_mass_solar":[0.012,0.012],"inclination_deg":[1.2,0.71],"host_radius_solar":[0.004,0.004],"host_temperature_k":[77,77],"semi_major_axis_km":[2094370.1897999998,897587.2241999999],"orbital_period_days":[0.0014,0.0014]},"host_mass_solar":0.569,"inclination_deg":89,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.5776,"planets_in_system":1,"discovery_facility":"K2","host_spectral_type":"M V","host_temperature_k":3861,"orbital_period_days":6.535,"transit_midpoint_bjd":2458373.0321,"equilibrium_temperature_k":558},"designations":[{"catalog":"Exoplanet","designation":"K2-417 b"},{"catalog":"Host star","designation":"K2-417"}],"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."}