{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T11:43:14.300Z","years_from_j2000":26.669,"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":"kepler-439-b","name":"Kepler-439 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":2469.1603343770516,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":280.8015188,"dec_deg":44.0339733,"epoch_ra_deg":281.003135,"epoch_dec_deg":44.05998,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-439","semi_major_axis_km":84223601.20409998,"periapsis_km":null,"mass_kg":3.3742748453021296e+25,"mass_msun":0.0000169697,"constellation":"Lyra","discovered":"2015","featured":false,"url":"https://spacecatalog.org/object/kepler-439-b","radius_km":14286.944000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-439","host_v_mag":14.654,"uncertainties":{"radius_km":[2870.1450000000004,1020.4960000000001],"distance_ly":[36.382743934302724,37.46884467209948],"host_mass_solar":[0.038,0.044],"inclination_deg":[0.12,0.05],"host_radius_solar":[0.04,0.076],"host_temperature_k":[100,100],"semi_major_axis_km":[11967829.656,24683648.6655],"orbital_period_days":[0.0018,0.0016]},"host_mass_solar":0.884,"inclination_deg":89.95,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.866,"planets_in_system":1,"discovery_facility":"Kepler","host_temperature_k":5431,"orbital_period_days":178.1396,"transit_midpoint_bjd":2455399.3987,"eccentricity_lower_limit":0.03,"equilibrium_temperature_k":291},"designations":[{"catalog":"Exoplanet","designation":"Kepler-439 b"},{"catalog":"Host star","designation":"Kepler-439"}],"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":"2026-09-01T22:58:55.274Z","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."}