{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.654","julian_year":2026.654,"time":"2026-08-27T17:05:55.943Z","years_from_j2000":26.654,"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":"eps-eri-b","name":"ε Eri b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":10.445484152756425,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":53.2284306,"dec_deg":-9.4581715,"epoch_ra_deg":53.552716,"epoch_dec_deg":-9.367194,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"ε Eri","semi_major_axis_km":528080483.5709999,"periapsis_km":null,"mass_kg":1.8981245997567207e+27,"mass_msun":0.000954594,"constellation":"Eridanus","discovered":"2000","featured":false,"url":"https://spacecatalog.org/object/eps-eri-b","radius_km":88017.78000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"ε Eri","host_v_mag":3.71548,"eccentricity":0.06,"uncertainties":{"mass_kg":[1.8981245997567207e+26,1.8981245997567207e+26],"distance_ly":[0.015753353043718707,0.015753353043718707],"eccentricity":[0.04,0.06],"host_mass_solar":[0.02,0.02],"inclination_deg":[5,6],"host_radius_solar":[0.011816,0.011816],"host_temperature_k":[57.69,57.69],"semi_major_axis_km":[5983914.828,5983914.828],"orbital_period_days":[30,30],"argument_of_periastron_deg":[105,62]},"host_mass_solar":0.82,"inclination_deg":40,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.759106,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"K2 V","host_temperature_k":5020.38,"orbital_period_days":2680,"periastron_epoch_bjd":2458017.5,"transit_midpoint_bjd":2457388,"equilibrium_temperature_k":112.26,"argument_of_periastron_deg":268},"designations":[{"catalog":"Exoplanet","designation":"eps Eri b"},{"catalog":"Host star","designation":"eps Eri"}],"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":"2026-08-27T16:03:54.983Z","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."}