{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T13:33:25.398Z","years_from_j2000":26.678,"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-117856","name":"HD 117856","class":"o9_7ii_iii_blue_bright_giant","category":"star","object_type":"O9.7II-III blue bright giant","mag":7.39,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":203.68087500000001,"dec_deg":-63.335453,"epoch_ra_deg":204.14183,"epoch_dec_deg":-63.473107,"epoch_moved_arcsec":0.157,"pm_ra_mas_yr":-4.94,"pm_dec_mas_yr":-3.23,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Centaurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-117856","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"13347-6320","companions":[{"measured":2016,"magnitude":11.38,"components":"AB","discoverer_code":"HDS1907","separation_arcsec":1.6,"position_angle_deg":356},{"measured":2016,"magnitude":13.11,"components":"AC","discoverer_code":"SNA  34","separation_arcsec":7.4,"position_angle_deg":91}],"spectral_type":"O9.7II-III","color_index_bv":0.207,"radial_velocity_km_s":-20,"spectral_type_source":"SIMBAD (2014ApJS..211...10S, quality C)","proper_motion_ra_mas_yr":-4.94,"proper_motion_dec_mas_yr":-3.23},"designations":[{"catalog":"HD","designation":"HD 117856"},{"catalog":"HIP","designation":"HIP 66253"}],"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."}