{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.673","julian_year":2026.673,"time":"2026-09-03T20:56:11.492Z","years_from_j2000":26.673,"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-312-c","name":"Kepler-312 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":2601.8146563220057,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":298.3957687,"dec_deg":42.4597712,"epoch_ra_deg":298.618476,"epoch_dec_deg":42.529107,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-312","semi_major_axis_km":22888474.2171,"periapsis_km":null,"mass_kg":6.031889546469293e+25,"mass_msun":0.0000303352,"constellation":"Cygnus","discovered":"2014","featured":false,"url":"https://spacecatalog.org/object/kepler-312-c","radius_km":20091.015,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-312","host_v_mag":13.01,"eccentricity":0,"uncertainties":{"radius_km":[3890.641,3890.641],"distance_ly":[44.39314457102595,45.932602673848976],"host_mass_solar":[0.02,0.025],"host_radius_solar":[0.283,0.283],"host_temperature_k":[100,100],"orbital_period_days":[0.000068,0.000068]},"host_mass_solar":1.314,"inclination_deg":89.06,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.467,"planets_in_system":2,"discovery_facility":"Kepler","host_temperature_k":6115,"orbital_period_days":19.747412,"transit_midpoint_bjd":2454980.1036,"equilibrium_temperature_k":754},"designations":[{"catalog":"Exoplanet","designation":"Kepler-312 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."}