{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T07:07:38.419Z","years_from_j2000":26.669,"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":"k2-89-b","name":"K2-89 b","class":"terrestrial_planet","category":"exoplanet","object_type":"Terrestrial planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":280.620381198198,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":57.0671234,"dec_deg":20.4594885,"epoch_ra_deg":57.457671,"epoch_dec_deg":20.542262,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"K2-89","semi_major_axis_km":2187120.8696339997,"periapsis_km":null,"mass_kg":1.0152685375245346e+24,"mass_msun":5.10593e-7,"constellation":"Taurus","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/k2-89-b","radius_km":3922.5315,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"K2-89","host_v_mag":14.162,"eccentricity":0.15,"uncertainties":{"radius_km":[510.24800000000005,510.24800000000005],"distance_ly":[1.0088016762778875,1.015650960209939],"eccentricity":[0.119964,0.197141],"host_mass_solar":[0.036,0.036],"inclination_deg":[1.41,2.27],"host_radius_solar":[0.033,0.033],"host_temperature_k":[51,51],"semi_major_axis_km":[76294.914057,76294.914057],"orbital_period_days":[0.000065,0.000065],"argument_of_periastron_deg":[137.817,86.6766]},"host_mass_solar":0.347,"inclination_deg":85.77,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.318,"planets_in_system":1,"discovery_facility":"K2","host_temperature_k":3691,"orbital_period_days":1.096026,"transit_midpoint_bjd":2457066.0066,"equilibrium_temperature_k":830.07,"argument_of_periastron_deg":51.29},"designations":[{"catalog":"Exoplanet","designation":"K2-89 b"},{"catalog":"Host star","designation":"K2-89"}],"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."}