{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-02T00:38:50.142Z","years_from_j2000":26.668,"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":"gl-686-b","name":"Gl 686 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":26.605488968212367,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":264.4764878,"dec_deg":18.5959509,"epoch_ra_deg":264.770513,"epoch_dec_deg":18.579646,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Gl 686","semi_major_axis_km":13613406.233699998,"periapsis_km":null,"mass_kg":3.955963995625009e+25,"mass_msun":0.0000198951,"constellation":"Hercules","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/gl-686-b","radius_km":15690.126,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Gl 686","host_v_mag":9.62,"eccentricity":0.05,"uncertainties":{"mass_kg":[2.5799765188858757e+24,2.5799765188858757e+24],"distance_ly":[0.007566827963028448,0.007566827963028448],"eccentricity":[0.03,0.03],"host_mass_solar":[0.017,0.017],"host_radius_solar":[0.013,0.013],"host_temperature_k":[51,51],"semi_major_axis_km":[149597.8707,149597.8707],"orbital_period_days":[0.0011,0.0011],"argument_of_periastron_deg":[153.673,153.673]},"host_mass_solar":0.426,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.427,"planets_in_system":1,"discovery_facility":"Roque de los Muchachos Observatory","host_spectral_type":"M1.0 V","host_temperature_k":3656,"orbital_period_days":15.53,"periastron_epoch_bjd":2457805.69,"transit_midpoint_bjd":2450606.8,"equilibrium_temperature_k":379,"argument_of_periastron_deg":197.062},"designations":[{"catalog":"Exoplanet","designation":"Gl 686 b"},{"catalog":"Host star","designation":"Gl 686"}],"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":"2026-09-01T22:58:55.274Z","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."}