{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T11:05:39.301Z","years_from_j2000":26.667,"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-20003-c","name":"HD 20003 c","class":"neptune_like_planet","category":"exoplanet","object_type":"Neptune-like planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":136.43643130095725,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":46.9090081,"dec_deg":-72.3219221,"epoch_ra_deg":46.916532,"epoch_dec_deg":-72.218132,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 20003","semi_major_axis_km":29381021.805479996,"periapsis_km":null,"mass_kg":8.623810401090751e+25,"mass_msun":0.0000433704,"constellation":"Hydrus","discovered":"2019","featured":false,"url":"https://spacecatalog.org/object/hd-20003-c","radius_km":24810.809,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 20003","host_v_mag":8.39,"eccentricity":0.1,"uncertainties":{"mass_kg":[8.301313336230016e+24,8.779086765653327e+24],"distance_ly":[0.1624258761029382,0.16275203248065495],"eccentricity":[0.07,0.08],"host_radius_solar":[0.01585,0.047725],"host_temperature_k":[27,27],"semi_major_axis_km":[1166863.3914599998,1017265.5207599999],"orbital_period_days":[0.0266,0.0239],"argument_of_periastron_deg":[34.56,45.86]},"host_mass_solar":0.875,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.921637,"planets_in_system":2,"discovery_facility":"La Silla Observatory","host_spectral_type":"G8 V","host_temperature_k":5494,"orbital_period_days":33.9239,"periastron_epoch_bjd":2455493.2516,"equilibrium_temperature_k":573.89,"argument_of_periastron_deg":53.33},"designations":[{"catalog":"Exoplanet","designation":"HD 20003 c"},{"catalog":"Host star","designation":"HD 20003"}],"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":"2026-08-30T09:56:50.739Z","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."}