{"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":"2026-09-07T07:54:22.381Z","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":"hd-12661-b","name":"HD 12661 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":123.44301352547761,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":31.1423525,"dec_deg":25.4135632,"epoch_ra_deg":31.522727,"epoch_dec_deg":25.542521,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 12661","semi_major_axis_km":125662211.38799998,"periapsis_km":null,"mass_kg":4.612465895610926e+27,"mass_msun":0.00231968,"constellation":"Aries","discovered":"2000","featured":false,"url":"https://spacecatalog.org/object/hd-12661-b","radius_km":84828.73000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 12661","host_v_mag":7.43,"eccentricity":0.38,"uncertainties":{"mass_kg":[2.657387758788188e+26,2.657387758788188e+26],"distance_ly":[0.20547851796154837,0.20645698709469856],"eccentricity":[0.01,0.01],"host_mass_solar":[0.1,0.1],"inclination_deg":[38,41],"host_radius_solar":[0.02,0.02],"host_temperature_k":[31,31],"semi_major_axis_km":[2991957.414,2991957.414],"orbital_period_days":[0.083,0.083],"argument_of_periastron_deg":[0.74,0.74]},"host_mass_solar":1.2,"inclination_deg":86,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.2,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_spectral_type":"K0","host_temperature_k":5645,"orbital_period_days":262.70862,"periastron_epoch_bjd":2454152.76,"transit_midpoint_bjd":2456079.28,"equilibrium_temperature_k":325.35,"argument_of_periastron_deg":-60.62},"designations":[{"catalog":"Exoplanet","designation":"HD 12661 b"}],"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."}