{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.686","julian_year":2026.686,"time":"2026-09-08T14:50:38.955Z","years_from_j2000":26.686,"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":"wasp-81-b","name":"WASP-81 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1299.7494730201083,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":304.2079924,"dec_deg":3.2939492,"epoch_ra_deg":304.545019,"epoch_dec_deg":3.376506,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"WASP-81","semi_major_axis_km":5846284.786955999,"periapsis_km":null,"mass_kg":1.3837397686832779e+27,"mass_msun":0.000695903,"constellation":"Aquila","discovered":"2017","featured":false,"url":"https://spacecatalog.org/object/wasp-81-b","radius_km":102162.24362410001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"WASP-81","host_v_mag":12.469,"uncertainties":{"mass_kg":[6.64346939697047e+25,6.833282808312482e+25],"radius_km":[3288.6376534,3646.0982679000003],"distance_ly":[22.468912860906453,23.26147285875814],"host_mass_solar":[0.058,0.059],"inclination_deg":[0.92,0.88],"host_radius_solar":[0.037,0.04],"host_temperature_k":[120,120],"semi_major_axis_km":[107710.466904,104718.50949],"orbital_period_days":[0.0000023,0.0000023]},"host_mass_solar":1.08,"inclination_deg":88.69,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.283,"planets_in_system":1,"discovery_facility":"Multiple Facilities","host_temperature_k":5870,"orbital_period_days":2.7164762,"transit_midpoint_bjd":2456195.57462,"eccentricity_upper_limit":0.066,"equilibrium_temperature_k":1623},"designations":[{"catalog":"Exoplanet","designation":"WASP-81 b"},{"catalog":"Host star","designation":"WASP-81"}],"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."}