{"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":"2026-09-08T12:46:46.369Z","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-433-d","name":"GJ 433 d","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":29.56464055196084,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":173.8619194,"dec_deg":-32.5436302,"epoch_ra_deg":174.194782,"epoch_dec_deg":-32.692175,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"GJ 433","semi_major_axis_km":26628420.984599996,"periapsis_km":null,"mass_kg":3.1192632773474374e+25,"mass_msun":0.0000156872,"constellation":"Hydra","discovered":"2020","featured":false,"url":"https://spacecatalog.org/object/gj-433-d","radius_km":13649.134000000002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"GJ 433","host_v_mag":9.81,"eccentricity":0.07,"uncertainties":{"mass_kg":[5.500366606235861e+24,5.500366606235861e+24],"distance_ly":[0.011969939062204484,0.011969939062204484],"eccentricity":[0.05,0.05],"host_radius_solar":[0.04,0.04],"host_temperature_k":[150,150],"semi_major_axis_km":[897587.2241999999,897587.2241999999],"orbital_period_days":[0.016,0.016],"argument_of_periastron_deg":[82,82]},"host_mass_solar":0.48,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.5,"planets_in_system":3,"discovery_facility":"Multiple Facilities","host_spectral_type":"M2V","host_temperature_k":3461,"orbital_period_days":36.059,"equilibrium_temperature_k":279.71,"argument_of_periastron_deg":159},"designations":[{"catalog":"Exoplanet","designation":"GJ 433 d"}],"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."}