{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.685","julian_year":2026.685,"time":"2026-09-08T04:23:15.442Z","years_from_j2000":26.685,"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":"hd-222155-b","name":"HD 222155 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":165.06056732213406,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":354.5025617,"dec_deg":48.9960191,"epoch_ra_deg":354.828154,"epoch_dec_deg":49.144748,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 222155","semi_major_axis_km":768933055.3979999,"periapsis_km":null,"mass_kg":3.4735680175547985e+27,"mass_msun":0.00174691,"constellation":"Andromeda","discovered":"2011","featured":false,"url":"https://spacecatalog.org/object/hd-222155-b","radius_km":85466.54000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 222155","host_v_mag":7.11716,"eccentricity":0.16,"uncertainties":{"mass_kg":[4.9351239593674735e+26,6.643436099148523e+26],"distance_ly":[0.2697313243717468,0.27103594988261376],"eccentricity":[0.22,0.22],"host_mass_solar":[0.1,0.1],"inclination_deg":[16,15],"host_radius_solar":[0.04,0.04],"host_temperature_k":[44,44],"semi_major_axis_km":[68815020.522,68815020.522],"orbital_period_days":[500,500],"argument_of_periastron_deg":[70,86]},"host_mass_solar":1.21,"inclination_deg":68,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.85,"planets_in_system":1,"discovery_facility":"Haute-Provence Observatory","host_spectral_type":"G2 V","host_temperature_k":5701,"orbital_period_days":3999,"periastron_epoch_bjd":2456319,"equilibrium_temperature_k":164.93,"argument_of_periastron_deg":163},"designations":[{"catalog":"Exoplanet","designation":"HD 222155 b"},{"catalog":"Host star","designation":"HD 222155"}],"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."}