{"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":"2026-09-03T10:40:49.898Z","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-189783","name":"HD 189783","class":"f5v_f7v_yellow_white_main_sequence_star","category":"star","object_type":"F5V+F7V yellow-white main-sequence star","mag":6.97,"mag_band":"V","abs_mag":2.439,"abs_mag_band":"V","distance_ly":262.8174614769073,"distance_method":"parallax","ra_deg":300.36125999999996,"dec_deg":10.748619,"epoch_ra_deg":300.681183,"epoch_dec_deg":10.822748,"epoch_moved_arcsec":2.327,"pm_ra_mas_yr":83.48,"pm_dec_mas_yr":25.3,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Aquila","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-189783","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"20014+1045","companions":[{"measured":2025,"magnitude":10.6,"components":"Aa,Ab","discoverer_code":"TOK  34","separation_arcsec":0.1,"position_angle_deg":337},{"measured":2024,"magnitude":8.02,"components":"AB","discoverer_code":"STF2613","separation_arcsec":3.4,"position_angle_deg":356}],"spectral_type":"F5V+F7V","color_index_bv":0.44,"luminosity_solar":9.212977276685555,"radial_velocity_km_s":-43,"spectral_type_source":"SIMBAD (1968AJ.....73..350M, quality C)","surface_temperature_k":6534,"proper_motion_ra_mas_yr":83.48,"proper_motion_dec_mas_yr":25.3,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 189783"},{"catalog":"HIP","designation":"HIP 98578"}],"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."}