{"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":"2026-09-07T12:57:10.018Z","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":"hip-12961-b","name":"HIP 12961 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":76.22600703618009,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":41.6800749,"dec_deg":-23.0860048,"epoch_ra_deg":41.982654,"epoch_dec_deg":-22.973016,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 12961","semi_major_axis_km":37399467.675,"periapsis_km":null,"mass_kg":6.833282808312482e+26,"mass_msun":0.000343656,"constellation":"Eridanus","discovered":"2010","featured":false,"url":"https://spacecatalog.org/object/hip-12961-b","radius_km":84190.92,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 12961","host_v_mag":10.25,"eccentricity":0.17,"uncertainties":{"mass_kg":[1.328693879394094e+26,1.328693879394094e+26],"distance_ly":[0.06001277349988079,0.06033892987759753],"eccentricity":[0.03,0.03],"host_mass_solar":[0.19,0.19],"host_radius_solar":[0.06,0.06],"host_temperature_k":[175,175],"semi_major_axis_km":[1495978.707,1495978.707],"orbital_period_days":[0.042,0.042],"argument_of_periastron_deg":[13,13]},"host_mass_solar":0.69,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.65,"planets_in_system":1,"discovery_facility":"La Silla Observatory","host_spectral_type":"M0","host_temperature_k":3901,"orbital_period_days":57.435,"equilibrium_temperature_k":303.32,"argument_of_periastron_deg":272},"designations":[{"catalog":"Exoplanet","designation":"HIP 12961 b"},{"catalog":"Host star","designation":"HIP 12961"}],"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."}