{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.665","julian_year":2026.665,"time":"2026-09-01T01:30:52.577Z","years_from_j2000":26.665,"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-296-d","name":"Kepler-296 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":544.6811507869616,"distance_method":"NASA Exoplanet Archive sy_dist (Morton+ 2016, 2016ApJ...822...86M)","ra_deg":286.5400278,"dec_deg":49.4372614,"epoch_ra_deg":286.715803,"epoch_dec_deg":49.477807,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-296","semi_major_axis_km":17652548.742599998,"periapsis_km":null,"mass_kg":2.998028269631272e+25,"mass_msun":0.0000150775,"constellation":"Draco","discovered":"2014","featured":false,"url":"https://spacecatalog.org/object/kepler-296-d","radius_km":13330.229,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-296","host_v_mag":16.363,"uncertainties":{"radius_km":[2040.9920000000002,2104.773],"distance_ly":[66.03688179630905,69.88878861714379],"host_mass_solar":[0.087,0.067],"host_radius_solar":[0.087,0.066],"host_temperature_k":[130,130],"semi_major_axis_km":[2991957.414,2991957.414],"orbital_period_days":[0.000057,0.000061]},"host_mass_solar":0.498,"inclination_deg":89.77,"stars_in_system":2,"discovery_method":"Transit","host_radius_solar":0.48,"planets_in_system":5,"discovery_facility":"Kepler","host_spectral_type":"M2 V","host_temperature_k":3740,"orbital_period_days":19.850291,"transit_midpoint_bjd":2454966.6496,"eccentricity_upper_limit":0.33,"equilibrium_temperature_k":403},"designations":[{"catalog":"Exoplanet","designation":"Kepler-296 d"}],"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":"2026-08-30T09:56:50.739Z","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."}