{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-02T01:24:21.395Z","years_from_j2000":26.668,"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-289-d","name":"Kepler-289 d","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":2297.569464060273,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":297.4653351,"dec_deg":42.8828517,"epoch_ra_deg":297.685152,"epoch_dec_deg":42.949995,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-289","semi_major_axis_km":49367297.331,"periapsis_km":null,"mass_kg":3.183165473532805e+25,"mass_msun":0.0000160086,"constellation":"Cygnus","discovered":"2014","featured":false,"url":"https://spacecatalog.org/object/kepler-289-d","radius_km":19325.643,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-289","host_v_mag":14.142,"uncertainties":{"mass_kg":[2.5083105044723793e+24,2.568032183150293e+24],"radius_km":[510.24800000000005,510.24800000000005],"distance_ly":[28.731115313067924,28.731115313067924],"host_mass_solar":[0.02,0.02],"inclination_deg":[0.04,0.04],"host_radius_solar":[0.02,0.02],"host_temperature_k":[38,38],"semi_major_axis_km":[2991957.414,2991957.414],"orbital_period_days":[0.0039,0.0044]},"host_mass_solar":1.08,"inclination_deg":89.31,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1,"planets_in_system":4,"discovery_facility":"Kepler","host_temperature_k":5990,"orbital_period_days":66.0282,"transit_midpoint_bjd":2454975.624,"equilibrium_temperature_k":502.81},"designations":[{"catalog":"Exoplanet","designation":"Kepler-289 d"},{"catalog":"Host star","designation":"Kepler-289"}],"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."}