{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.685","julian_year":2026.685,"time":"2026-09-08T01:02:42.167Z","years_from_j2000":26.685,"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-tau-b","name":"ε Tau b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":155.01729921437794,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":67.1546573,"dec_deg":19.1802782,"epoch_ra_deg":67.546728,"epoch_dec_deg":19.240013,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"ε Tau","semi_major_axis_km":280944801.17459995,"periapsis_km":null,"mass_kg":1.3647515872250822e+28,"mass_msun":0.00686353,"constellation":"Taurus","discovered":"2006","featured":false,"url":"https://spacecatalog.org/object/eps-tau-b","radius_km":81001.87,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"ε Tau","host_v_mag":3.523,"eccentricity":0.076,"uncertainties":{"mass_kg":[1.0629497757443202e+26,1.0629497757443202e+26],"distance_ly":[6.041557662636096,6.041557662636096],"eccentricity":[0.008,0.009],"host_mass_solar":[0.25,0.17],"host_radius_solar":[0.36,0.41],"semi_major_axis_km":[149597.8707,149597.8707],"orbital_period_days":[0.33,0.26],"argument_of_periastron_deg":[6.07,6.82]},"host_mass_solar":2.57,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":12.35,"planets_in_system":1,"discovery_facility":"Okayama Astrophysical Observatory","host_spectral_type":"K0 III","host_temperature_k":4877,"orbital_period_days":585.82,"periastron_epoch_bjd":2453492.3,"equilibrium_temperature_k":603.08,"argument_of_periastron_deg":107.9},"designations":[{"catalog":"Exoplanet","designation":"eps Tau b"},{"catalog":"Host star","designation":"eps Tau"}],"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."}