{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.671","julian_year":2026.671,"time":"2026-09-03T00:33:29.671Z","years_from_j2000":26.671,"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-990-c","name":"Kepler-990 c","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":2616.3057841839604,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":297.9381813,"dec_deg":46.8813194,"epoch_ra_deg":298.139988,"epoch_dec_deg":46.949557,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-990","semi_major_axis_km":1843045.7670239997,"periapsis_km":null,"mass_kg":1.7677616888662482e+25,"mass_msun":0.00000889033,"constellation":"Cygnus","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/kepler-990-c","radius_km":9758.493,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-990","host_v_mag":14.716,"eccentricity":0,"uncertainties":{"radius_km":[1211.8390000000002,2232.335],"distance_ly":[40.13028071426811,40.13028071426811],"host_mass_solar":[0.087,0.122],"host_radius_solar":[0.142,0.269],"host_temperature_k":[213.6,211.07],"semi_major_axis_km":[17951.744484,17951.744484],"orbital_period_days":[6.75e-7,6.75e-7]},"host_mass_solar":1.05,"inclination_deg":82.87,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.08,"planets_in_system":2,"discovery_facility":"Kepler","host_temperature_k":5948,"orbital_period_days":0.538354308,"transit_midpoint_bjd":2454964.64931,"equilibrium_temperature_k":2386},"designations":[{"catalog":"Exoplanet","designation":"Kepler-990 c"},{"catalog":"Host star","designation":"Kepler-990"}],"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."}