{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.677","julian_year":2026.677,"time":"2026-09-05T03:25:58.037Z","years_from_j2000":26.677,"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-183263-c","name":"HD 183263 c","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":176.7620796854777,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":292.1022982,"dec_deg":8.3579183,"epoch_ra_deg":292.425906,"epoch_dec_deg":8.412453,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 183263","semi_major_axis_km":835504107.8594999,"periapsis_km":null,"mass_kg":1.767154002373507e+28,"mass_msun":0.00888727,"constellation":"Aquila","discovered":"2008","featured":false,"url":"https://spacecatalog.org/object/hd-183263-c","radius_km":79726.25,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 183263","host_v_mag":7.86,"eccentricity":0.051,"uncertainties":{"mass_kg":[3.458383020732856e+27,2.88894564080584e+27],"distance_ly":[0.36757823768676984,0.3688828631976368],"eccentricity":[0.01,0.01],"host_mass_solar":[0.136,0.136],"inclination_deg":[32.077,63.943],"host_radius_solar":[0.02,0.02],"host_temperature_k":[27,27],"semi_major_axis_km":[37549065.5457,34108314.5196],"orbital_period_days":[17.90216,18.57225],"argument_of_periastron_deg":[11.723,11.839]},"host_mass_solar":1.06,"inclination_deg":73.718,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.23,"planets_in_system":2,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G2 IV","host_temperature_k":5948,"orbital_period_days":4667.97841,"periastron_epoch_bjd":2451487.545,"transit_midpoint_bjd":2457195.7,"equilibrium_temperature_k":134.6,"argument_of_periastron_deg":297.163},"designations":[{"catalog":"Exoplanet","designation":"HD 183263 c"}],"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."}