{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.665","julian_year":2026.665,"time":"2026-09-01T01:08:56.718Z","years_from_j2000":26.665,"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":"11-com-b","name":"11 Com b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":303.9275159498365,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":185.1787793,"dec_deg":17.7932516,"epoch_ra_deg":185.519041,"epoch_dec_deg":17.644228,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"11 Com","semi_major_axis_km":176226291.68459997,"periapsis_km":null,"mass_kg":2.935259881064987e+28,"mass_msun":0.0147618,"constellation":"Coma Berenices","discovered":"2007","featured":false,"url":"https://spacecatalog.org/object/11-com-b","radius_km":77812.82,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"11 Com","host_v_mag":4.72307,"eccentricity":0.238,"uncertainties":{"mass_kg":[2.3726557499945094e+26,2.3346932576410446e+26],"distance_ly":[6.27459639451471,6.27459639451471],"eccentricity":[0.007,0.007],"host_mass_solar":[0.63,0.64],"host_radius_solar":[2.45,2.85],"orbital_period_days":[0.05,0.06],"argument_of_periastron_deg":[1.8,1.7]},"host_mass_solar":2.09,"stars_in_system":2,"discovery_method":"Radial Velocity","host_radius_solar":13.76,"planets_in_system":1,"discovery_facility":"Xinglong Station","host_spectral_type":"G8 III","host_temperature_k":4874,"orbital_period_days":323.21,"periastron_epoch_bjd":2454519.4,"equilibrium_temperature_k":803.26,"argument_of_periastron_deg":91.33},"designations":[{"catalog":"Exoplanet","designation":"11 Com b"},{"catalog":"Host star","designation":"11 Com"}],"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":"2026-08-30T09:56:50.739Z","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."}