{"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":"2026-09-04T17:27:06.494Z","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-75784-c","name":"HD 75784 c","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":278.642242767346,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":133.0992289,"dec_deg":13.2330548,"epoch_ra_deg":133.469201,"epoch_dec_deg":13.13221,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 75784","semi_major_axis_km":1256622113.8799999,"periapsis_km":null,"mass_kg":1.0705476399689556e+28,"mass_msun":0.00538394,"constellation":"Cancer","discovered":"2018","featured":false,"url":"https://spacecatalog.org/object/hd-75784-c","radius_km":81639.68000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 75784","host_v_mag":7.84,"eccentricity":0.489,"uncertainties":{"mass_kg":[1.3666565616624965e+27,1.3666565616624965e+27],"distance_ly":[1.714114843090345,1.714114843090345],"eccentricity":[0.092,0.092],"semi_major_axis_km":[209437018.97999996,209437018.97999996],"orbital_period_days":[2000,2000],"argument_of_periastron_deg":[12,12]},"host_mass_solar":1.26,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":3.4,"planets_in_system":2,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G5","host_temperature_k":4867,"orbital_period_days":7900,"periastron_epoch_bjd":2431200,"equilibrium_temperature_k":149.31,"argument_of_periastron_deg":325},"designations":[{"catalog":"Exoplanet","designation":"HD 75784 c"},{"catalog":"Host star","designation":"HD 75784"}],"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."}