{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T07:54:58.201Z","years_from_j2000":26.672,"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-9311","name":"HD 9311","class":"b5ib_blue_white_supergiant","category":"star","object_type":"B5Ib blue-white supergiant","mag":7.23,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":23.308365,"dec_deg":60.686437,"epoch_ra_deg":23.75522,"epoch_dec_deg":60.824404,"epoch_moved_arcsec":0.044,"pm_ra_mas_yr":-1.49,"pm_dec_mas_yr":-0.72,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cassiopeia","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-9311","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"01332+6041","companions":[{"measured":2024,"magnitude":9.9,"components":"AB","discoverer_code":"STF 131","separation_arcsec":14.1,"position_angle_deg":143},{"measured":2021,"magnitude":11.8,"components":"AC","discoverer_code":"STF 131","separation_arcsec":28.3,"position_angle_deg":145},{"measured":2014,"magnitude":11.78,"components":"AD","discoverer_code":"FLE   2","separation_arcsec":46.3,"position_angle_deg":121},{"measured":2014,"magnitude":10.58,"components":"AE","discoverer_code":"FLE   2","separation_arcsec":82.1,"position_angle_deg":136}],"spectral_type":"B5Ib","color_index_bv":0.287,"radial_velocity_km_s":-40.3,"spectral_type_source":"SIMBAD (2024A&A...690A.176N, quality C)","proper_motion_ra_mas_yr":-1.49,"proper_motion_dec_mas_yr":-0.72},"designations":[{"catalog":"HD","designation":"HD 9311"},{"catalog":"HIP","designation":"HIP 7232"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"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."}