{"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":"2026-09-02T22:19:10.415Z","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-47-c","name":"Kepler-47 c","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":3343.168102872163,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":295.2978883,"dec_deg":46.9204303,"epoch_ra_deg":295.496298,"epoch_dec_deg":46.982462,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-47","semi_major_axis_km":144182427.78065997,"periapsis_km":null,"mass_kg":1.893177214089867e+25,"mass_msun":0.00000952106,"constellation":"Cygnus","discovered":"2012","featured":false,"url":"https://spacecatalog.org/object/kepler-47-c","radius_km":29658.165000000005,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-47","host_v_mag":15.31,"eccentricity":0.044,"uncertainties":{"mass_kg":[7.465209834739224e+24,1.3019325951785207e+25],"radius_km":[446.46700000000004,574.029],"distance_ly":[99.94899116940744,99.94899116940744],"eccentricity":[0.019,0.029],"host_mass_solar":[0.015,0.013],"inclination_deg":[0.0042,0.0055],"host_radius_solar":[0.005,0.005],"host_temperature_k":[100,100],"semi_major_axis_km":[658230.63108,613351.26987],"orbital_period_days":[0.027,0.062],"argument_of_periastron_deg":[67,40]},"host_mass_solar":0.957,"inclination_deg":90.1925,"stars_in_system":2,"discovery_method":"Transit","host_radius_solar":0.936,"planets_in_system":3,"discovery_facility":"Kepler","host_temperature_k":5636,"orbital_period_days":303.227,"transit_midpoint_bjd":2454944.362,"equilibrium_temperature_k":267.82,"argument_of_periastron_deg":306},"designations":[{"catalog":"Exoplanet","designation":"Kepler-47 c"}],"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."}