{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.676","julian_year":2026.676,"time":"2026-09-04T23:02:21.882Z","years_from_j2000":26.676,"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":"hd-40979-b","name":"HD 40979 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":111.18116450521664,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":91.1253346,"dec_deg":44.2597855,"epoch_ra_deg":91.615173,"epoch_dec_deg":44.258498,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 40979","semi_major_axis_km":127158190.09499998,"periapsis_km":null,"mass_kg":8.864286309672026e+27,"mass_msun":0.00445798,"constellation":"Auriga","discovered":"2002","featured":false,"url":"https://spacecatalog.org/object/hd-40979-b","radius_km":82277.49,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 40979","host_v_mag":6.75512,"eccentricity":0.25,"uncertainties":{"mass_kg":[6.453655985628456e+26,6.453655985628456e+26],"distance_ly":[0.1389426169073327,0.13926877328504944],"eccentricity":[0.01,0.01],"host_mass_solar":[0.15,0.15],"host_radius_solar":[0.02,0.02],"host_temperature_k":[25,25],"semi_major_axis_km":[1495978.707,1495978.707],"orbital_period_days":[0.23,0.23],"argument_of_periastron_deg":[4.1,4.1]},"host_mass_solar":1.45,"stars_in_system":3,"discovery_method":"Radial Velocity","host_radius_solar":1.21,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"F8 V","host_temperature_k":6165,"orbital_period_days":264.14999,"periastron_epoch_bjd":2453919,"transit_midpoint_bjd":2452405.1,"equilibrium_temperature_k":354.69,"argument_of_periastron_deg":323.4},"designations":[{"catalog":"Exoplanet","designation":"HD 40979 b"},{"catalog":"Host star","designation":"HD 40979"}],"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."}