{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.677","julian_year":2026.677,"time":"2026-09-05T06:50:28.895Z","years_from_j2000":26.677,"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":"k2-197-b","name":"K2-197 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":807.6838690864118,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":202.3934779,"dec_deg":-7.3739779,"epoch_ra_deg":202.74484,"epoch_dec_deg":-7.512934,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-197","semi_major_axis_km":12057588.378419999,"periapsis_km":null,"mass_kg":4.228294850396297e+25,"mass_msun":0.0000212647,"constellation":"Virgo","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/k2-197-b","radius_km":16327.936000000002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"K2-197","host_v_mag":12.199,"uncertainties":{"radius_km":[1020.4960000000001,1020.4960000000001],"distance_ly":[7.661413312566303,7.804922118761669],"host_mass_solar":[0.02,0.02],"inclination_deg":[1.88454,1.08066],"host_radius_solar":[0.01,0.01],"host_temperature_k":[58,58],"semi_major_axis_km":[104718.50949,89758.72241999999],"orbital_period_days":[0.000686,0.00071]},"host_mass_solar":1,"inclination_deg":88.50928,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.93,"planets_in_system":1,"discovery_facility":"K2","host_temperature_k":5667,"orbital_period_days":8.357881,"transit_midpoint_bjd":2457218.18248,"equilibrium_temperature_k":848},"designations":[{"catalog":"Exoplanet","designation":"K2-197 b"},{"catalog":"Host star","designation":"K2-197"}],"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."}