{"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":"2026-09-08T13:40:20.917Z","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":"gj-163-c","name":"GJ 163 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":49.34256760287753,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":62.3228353,"dec_deg":-53.3711768,"epoch_ra_deg":62.49047,"epoch_dec_deg":-53.299833,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"GJ 163","semi_major_axis_km":18759572.98578,"periapsis_km":null,"mass_kg":4.061074150098138e+25,"mass_msun":0.0000204237,"constellation":"Dorado","discovered":"2013","featured":false,"url":"https://spacecatalog.org/object/gj-163-c","radius_km":15945.25,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"GJ 163","host_v_mag":11.79,"eccentricity":0.099,"uncertainties":{"mass_kg":[5.374951081012241e+24,5.374951081012241e+24],"distance_ly":[0.023483259195605524,0.023483259195605524],"eccentricity":[0.086,0.086],"host_mass_solar":[0.02,0.02],"host_radius_solar":[0.012214,0.012214],"host_temperature_k":[100,100],"semi_major_axis_km":[14959.78707,14959.78707],"orbital_period_days":[0.0255,0.0255],"argument_of_periastron_deg":[79.87,79.87]},"host_mass_solar":0.4,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.409738,"planets_in_system":3,"discovery_facility":"La Silla Observatory","host_spectral_type":"M","host_temperature_k":3500,"orbital_period_days":25.63058,"periastron_epoch_bjd":2455057.7,"equilibrium_temperature_k":305.07,"argument_of_periastron_deg":227},"designations":[{"catalog":"Exoplanet","designation":"GJ 163 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."}