{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T12:09:10.733Z","years_from_j2000":26.678,"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":"corot-18-b","name":"CoRoT-18 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":2494.7342559538215,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":98.1724172,"dec_deg":-0.0316045,"epoch_ra_deg":98.516463,"epoch_dec_deg":-0.051042,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"CoRoT-18","semi_major_axis_km":4413137.185649999,"periapsis_km":null,"mass_kg":6.586226167957689e+27,"mass_msun":0.00331231,"constellation":"Monoceros","discovered":"2011","featured":false,"url":"https://spacecatalog.org/object/corot-18-b","radius_km":93630.508,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"CoRoT-18","host_v_mag":14.868,"uncertainties":{"mass_kg":[7.212587133931648e+26,7.212587133931648e+26],"radius_km":[12883.762,12883.762],"distance_ly":[84.09616043048511,90.06482214270153],"host_mass_solar":[0.15,0.15],"inclination_deg":[0.9,1.4],"host_radius_solar":[0.13,0.13],"host_temperature_k":[100,100],"semi_major_axis_km":[239356.59312,239356.59312],"orbital_period_days":[0.0000028,0.0000028]},"host_mass_solar":0.95,"inclination_deg":86.5,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1,"planets_in_system":1,"discovery_facility":"CoRoT","host_spectral_type":"G9 V","host_temperature_k":5440,"orbital_period_days":1.9000693,"transit_midpoint_bjd":2455321.72412,"eccentricity_upper_limit":0.08,"equilibrium_temperature_k":1550},"designations":[{"catalog":"Exoplanet","designation":"CoRoT-18 b"},{"catalog":"Host star","designation":"CoRoT-18"}],"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."}