{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.683","julian_year":2026.683,"time":"2026-09-07T12:50:33.246Z","years_from_j2000":26.683,"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":"gj-1151-c","name":"GJ 1151 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":26.210741904261795,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":177.7304866,"dec_deg":48.3732334,"epoch_ra_deg":178.083456,"epoch_dec_deg":48.223837,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"GJ 1151","semi_major_axis_km":85480223.31797999,"periapsis_km":null,"mass_kg":6.342442275594444e+25,"mass_msun":0.0000318971,"constellation":"Ursa Major","discovered":"2023","featured":false,"url":"https://spacecatalog.org/object/gj-1151-c","radius_km":20728.825,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"GJ 1151","host_v_mag":13.76,"uncertainties":{"mass_kg":[8.779086765653327e+24,7.823539906806707e+24],"distance_ly":[0.025146656721960918,0.025179272359732593],"host_mass_solar":[0.0093,0.0093],"host_radius_solar":[0.0042,0.0042],"host_temperature_k":[40,40],"semi_major_axis_km":[957426.37248,792868.71471],"orbital_period_days":[6.5,5.4]},"host_mass_solar":0.1639,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.1781,"planets_in_system":1,"discovery_facility":"Multiple Facilities","host_spectral_type":"M 4.5V","host_temperature_k":3280,"orbital_period_days":389.7,"transit_midpoint_bjd":2457798.67,"equilibrium_temperature_k":88.3},"designations":[{"catalog":"Exoplanet","designation":"GJ 1151 c"},{"catalog":"Host star","designation":"GJ 1151"}],"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."}