{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.654","julian_year":2026.654,"time":"2026-08-27T22:35:34.154Z","years_from_j2000":26.654,"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":"hn-peg-b","name":"HN Peg b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":59.09496945298587,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":326.1315705,"dec_deg":14.7714524,"epoch_ra_deg":326.453043,"epoch_dec_deg":14.894489,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HN Peg","semi_major_axis_km":115639154051.09999,"periapsis_km":null,"mass_kg":4.175482969941417e+28,"mass_msun":0.0209991,"constellation":"Pegasus","discovered":"2006","featured":false,"url":"https://spacecatalog.org/object/hn-peg-b","radius_km":75113.60808,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HN Peg","host_v_mag":5.97707,"uncertainties":{"mass_kg":[1.7894944077371411e+28,1.7894944077371411e+28],"radius_km":[4172.999487,9736.998803],"distance_ly":[0.06555743192106543,0.06555743192106543],"host_mass_solar":[0.140491,0.140394],"host_radius_solar":[0.02879,0.030893],"host_temperature_k":[7,14],"semi_major_axis_km":[1944772319.1,1944772319.1]},"host_mass_solar":1.08,"stars_in_system":1,"discovery_method":"Imaging","host_radius_solar":1.006954,"planets_in_system":1,"discovery_facility":"Spitzer Space Telescope","host_spectral_type":"G0 V","host_temperature_k":6186,"equilibrium_temperature_k":10.77},"designations":[{"catalog":"Exoplanet","designation":"HN Peg b"},{"catalog":"Host star","designation":"HN Peg"}],"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":"2026-08-27T19:16:43.430Z","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."}