{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T18:27:08.209Z","years_from_j2000":26.681,"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-18143-b","name":"HD 18143 b","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":73.46444098605244,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":43.9140248,"dec_deg":26.8723829,"epoch_ra_deg":44.310286,"epoch_dec_deg":26.981364,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 18143","semi_major_axis_km":13164612.621599998,"periapsis_km":null,"mass_kg":6.453623640367284e+25,"mass_msun":0.0000324562,"constellation":"Aries","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/hd-18143-b","radius_km":20920.168,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 18143","host_v_mag":7.518,"eccentricity":0.224,"uncertainties":{"mass_kg":[1.3286872204269213e+25,9.490623028644443e+24],"distance_ly":[0.07501596687485099,0.07501596687485099],"eccentricity":[0.122,0.171],"host_mass_solar":[0.103,0.103],"host_radius_solar":[0.03,0.03],"host_temperature_k":[141,114.96],"semi_major_axis_km":[598391.4828,448793.61209999997],"orbital_period_days":[0.00263,0.00213],"argument_of_periastron_deg":[73.038,87.534]},"host_mass_solar":0.85,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.87,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_spectral_type":"K2","host_temperature_k":5078,"orbital_period_days":10.2851,"periastron_epoch_bjd":2427146.014,"equilibrium_temperature_k":769.92,"argument_of_periastron_deg":60.123},"designations":[{"catalog":"Exoplanet","designation":"HD 18143 b"}],"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."}