{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.680","julian_year":2026.68,"time":"2026-09-06T08:22:03.743Z","years_from_j2000":26.68,"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":"kepler-631-b","name":"Kepler-631 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":2485.2007050331613,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":296.885724,"dec_deg":40.2281717,"epoch_ra_deg":297.11619,"epoch_dec_deg":40.294029,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-631","semi_major_axis_km":20969133.536018997,"periapsis_km":null,"mass_kg":5.2256468843174565e+25,"mass_msun":0.0000262805,"constellation":"Cygnus","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/kepler-631-b","radius_km":18496.49,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-631","host_v_mag":13.563,"eccentricity":0,"uncertainties":{"radius_km":[1466.9630000000002,2040.9920000000002],"distance_ly":[35.190642373748034,35.190642373748034],"host_mass_solar":[0.05,0.053],"host_radius_solar":[0.103,0.145],"host_temperature_k":[75.47,85.62],"semi_major_axis_km":[221404.84863599998,221404.84863599998],"orbital_period_days":[0.0000377,0.0000377]},"host_mass_solar":1.24,"inclination_deg":89.84,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.33,"planets_in_system":1,"discovery_facility":"Kepler","host_temperature_k":6185,"orbital_period_days":17.97979059,"transit_midpoint_bjd":2455015.24346,"equilibrium_temperature_k":828},"designations":[{"catalog":"Exoplanet","designation":"Kepler-631 b"},{"catalog":"Host star","designation":"Kepler-631"}],"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."}