{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.680","julian_year":2026.68,"time":"2026-09-06T07:31:06.811Z","years_from_j2000":26.68,"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-27631-b","name":"HD 27631 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":164.01164841139703,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":64.9392168,"dec_deg":-41.9606604,"epoch_ra_deg":65.162496,"epoch_dec_deg":-41.895499,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 27631","semi_major_axis_km":484996296.80939996,"periapsis_km":null,"mass_kg":2.961074375620484e+27,"mass_msun":0.00148917,"constellation":"Horologium","discovered":"2012","featured":false,"url":"https://spacecatalog.org/object/hd-27631-b","radius_km":86104.35,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 27631","host_v_mag":8.26,"eccentricity":0.141,"uncertainties":{"mass_kg":[2.8471868996350808e+26,3.7962491995134415e+26],"distance_ly":[0.26777438610544635,0.26842669886087983],"eccentricity":[0.065,0.062],"host_mass_solar":[0.032,0.032],"inclination_deg":[15,11],"host_radius_solar":[0.033,0.033],"host_temperature_k":[36,36],"semi_major_axis_km":[10172655.2076,10471850.949000001],"orbital_period_days":[50.34,54.11],"argument_of_periastron_deg":[30.158,33.335]},"host_mass_solar":0.944,"inclination_deg":74,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.923,"planets_in_system":1,"discovery_facility":"La Silla Observatory","host_spectral_type":"G3 IV/V","host_temperature_k":5737,"orbital_period_days":2198.14,"periastron_epoch_bjd":2456086,"equilibrium_temperature_k":147.61,"argument_of_periastron_deg":122.642},"designations":[{"catalog":"Exoplanet","designation":"HD 27631 b"},{"catalog":"Host star","designation":"HD 27631"}],"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."}