{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T22:44:45.718Z","years_from_j2000":26.687,"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":"toi-4559-b","name":"TOI-4559 b","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":103.18087471620265,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":211.0135378,"dec_deg":-30.0141252,"epoch_ra_deg":211.401593,"epoch_dec_deg":-30.143282,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"TOI-4559","semi_major_axis_km":5370563.55813,"periapsis_km":null,"mass_kg":1.5467914777579671e+25,"mass_msun":0.00000777904,"constellation":"Hydra","discovered":"2024","featured":false,"url":"https://spacecatalog.org/object/toi-4559-b","radius_km":9025.0115,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"TOI-4559","host_v_mag":13.115,"uncertainties":{"radius_km":[714.3472,803.6406000000001],"distance_ly":[0.24086648494381502,0.24086648494381502],"host_mass_solar":[0.026,0.027],"inclination_deg":[1.49,0.96],"host_radius_solar":[0.015,0.017],"host_temperature_k":[83,73],"semi_major_axis_km":[119678.29656,119678.29656],"orbital_period_days":[0.000332,0.000314]},"host_mass_solar":0.392,"inclination_deg":88.64,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.374,"planets_in_system":1,"discovery_facility":"Transiting Exoplanet Survey Satellite (TESS)","host_temperature_k":3558,"orbital_period_days":3.965991,"transit_midpoint_bjd":2459335.3447,"equilibrium_temperature_k":554.16},"designations":[{"catalog":"Exoplanet","designation":"TOI-4559 b"},{"catalog":"Host star","designation":"TOI-4559"}],"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."}