{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T18:51:20.309Z","years_from_j2000":26.667,"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-977-b","name":"Kepler-977 b","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":1855.0176598277553,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":291.5161959,"dec_deg":42.2480736,"epoch_ra_deg":291.733094,"epoch_dec_deg":42.301005,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Kepler-977","semi_major_axis_km":24234855.0534,"periapsis_km":null,"mass_kg":4.401487718562246e+25,"mass_msun":0.0000221357,"constellation":"Lyra","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/kepler-977-b","radius_km":16710.622000000003,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Kepler-977","host_v_mag":14.754,"eccentricity":0,"uncertainties":{"radius_km":[1084.277,1084.277],"distance_ly":[20.91314693919759,20.91314693919759],"host_mass_solar":[0.05,0.041],"host_radius_solar":[0.045,0.055],"host_temperature_k":[105.24,84.55],"orbital_period_days":[0.00006393,0.00006393]},"host_mass_solar":0.87,"inclination_deg":89.99,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.83,"planets_in_system":1,"discovery_facility":"Kepler","host_temperature_k":5315,"orbital_period_days":26.85328322,"transit_midpoint_bjd":2454976.31116,"equilibrium_temperature_k":544},"designations":[{"catalog":"Exoplanet","designation":"Kepler-977 b"},{"catalog":"Host star","designation":"Kepler-977"}],"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."}