{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.666","julian_year":2026.666,"time":"2026-09-01T05:29:09.663Z","years_from_j2000":26.666,"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-218917","name":"HD 218917","class":"f5_yellow_white_star","category":"star","object_type":"F5 yellow-white star","mag":7.9,"mag_band":"V","abs_mag":1.776,"abs_mag_band":"V","distance_ly":547.2421306647934,"distance_method":"parallax","ra_deg":347.85777,"dec_deg":38.219811,"epoch_ra_deg":348.176024,"epoch_dec_deg":38.36554,"epoch_moved_arcsec":1.6,"pm_ra_mas_yr":60.01,"pm_dec_mas_yr":1.09,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Andromeda","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-218917","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"23114+3813","companions":[{"measured":2011,"magnitude":9.16,"components":"AB","discoverer_code":"HO  197","separation_arcsec":0.2,"position_angle_deg":275},{"measured":2016,"magnitude":10.34,"components":"AB,C","discoverer_code":"HO  197","separation_arcsec":36.4,"position_angle_deg":320},{"measured":2016,"magnitude":9.83,"components":"AB,D","discoverer_code":"HO  197","separation_arcsec":56.8,"position_angle_deg":279}],"spectral_type":"F5","color_index_bv":0.478,"luminosity_solar":16.96680232346464,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_temperature_k":6641,"proper_motion_ra_mas_yr":60.01,"proper_motion_dec_mas_yr":1.09,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 218917"},{"catalog":"HIP","designation":"HIP 114504"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}