{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.688","julian_year":2026.688,"time":"2026-09-09T07:50:49.274Z","years_from_j2000":26.688,"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":"kmt-2023-blg-1866l-b","name":"KMT-2023-BLG-1866L b","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":20254.311056209765,"distance_method":"NASA Exoplanet Archive sy_dist (Han+ 2024, 2024A&A...687A.241H)","ra_deg":273.48225,"dec_deg":-28.4473889,"epoch_ra_deg":273.907521,"epoch_dec_deg":-28.440068,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"KMT-2023-BLG-1866L","semi_major_axis_km":393442399.9409999,"periapsis_km":null,"mass_kg":1.5706801492291326e+25,"mass_msun":0.00000789918,"constellation":"Sagittarius","discovered":"2024","featured":false,"url":"https://spacecatalog.org/object/kmt-2023-blg-1866l-b","radius_km":9120.683,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"KMT-2023-BLG-1866L","uncertainties":{"mass_kg":[4.0610741500981384e+24,2.5083105044723793e+24],"distance_ly":[2609.2510217339473,2837.560486135668],"host_mass_solar":[0.13,0.08],"semi_major_axis_km":[50863276.038,55351212.158999994]},"host_mass_solar":0.51,"stars_in_system":1,"discovery_method":"Microlensing","planets_in_system":1,"discovery_facility":"KMTNet"},"designations":[{"catalog":"Exoplanet","designation":"KMT-2023-BLG-1866L b"},{"catalog":"Host star","designation":"KMT-2023-BLG-1866L"}],"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."}