{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-01T21:13:30.560Z","years_from_j2000":26.668,"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-185657","name":"HD 185657","class":"g6v_yellow_main_sequence_star","category":"star","object_type":"G6V yellow main-sequence star","mag":6.47,"mag_band":"V","abs_mag":0.735,"abs_mag_band":"V","distance_ly":457.4424736571755,"distance_method":"parallax","ra_deg":294.486255,"dec_deg":49.284416,"epoch_ra_deg":294.671432,"epoch_dec_deg":49.345562,"epoch_moved_arcsec":4.001,"pm_ra_mas_yr":36.44,"pm_dec_mas_yr":145.53,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cygnus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-185657","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"19379+4917","companions":[{"measured":2023,"magnitude":10.19,"components":"AB","discoverer_code":"HJ 1428","separation_arcsec":36.4,"position_angle_deg":230},{"measured":2023,"magnitude":10.97,"components":"AC","discoverer_code":"HJ 1428","separation_arcsec":65,"position_angle_deg":243}],"spectral_type":"G6V","uncertainties":{"metallicity_fe_h":[0.055,0.055]},"color_index_bv":0.99,"luminosity_solar":44.25883723626264,"metallicity_fe_h":-0.455,"radial_velocity_km_s":-85,"spectral_type_source":"SIMBAD (2007MNRAS.374..664C, quality D)","surface_gravity_log_g":3,"surface_temperature_k":4782,"metallicity_fe_h_source":"Median of 2 spectroscopic determinations in 2 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":36.44,"proper_motion_dec_mas_yr":145.53,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 185657"},{"catalog":"HIP","designation":"HIP 96572"},{"catalog":"HR","designation":"HR 7477"}],"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."}