{"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":"2026-09-05T16:05:44.835Z","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-176668","name":"HD 176668","class":"g6iii_yellow_giant","category":"star","object_type":"G6III yellow giant","mag":6.5,"mag_band":"V","abs_mag":1.602,"abs_mag_band":"V","distance_ly":311.2177633045611,"distance_method":"parallax","ra_deg":284.32224,"dec_deg":62.396773,"epoch_ra_deg":284.388135,"epoch_dec_deg":62.43133,"epoch_moved_arcsec":1.098,"pm_ra_mas_yr":5.86,"pm_dec_mas_yr":-40.72,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Draco","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-176668","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"18573+6224","age_years":784537430,"companions":[{"measured":2015,"magnitude":9.61,"components":"AB","discoverer_code":"STF2440","separation_arcsec":17.4,"position_angle_deg":122},{"measured":2015,"magnitude":13.45,"components":"AD","discoverer_code":"WAL  98","separation_arcsec":53.9,"position_angle_deg":71},{"measured":2015,"magnitude":10.92,"components":"AC","discoverer_code":"STF2440","separation_arcsec":161,"position_angle_deg":60}],"mass_solar":2.3,"radius_solar":6.887,"spectral_type":"G6III","uncertainties":{"metallicity_fe_h":[0.1,0.1]},"color_index_bv":0.927,"luminosity_solar":19.915902890576117,"metallicity_fe_h":0.03,"radial_velocity_km_s":-8,"spectral_type_source":"SIMBAD (1950ApJ...111..221W, quality C)","surface_gravity_log_g":3.025,"surface_temperature_k":5192,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":5.86,"proper_motion_dec_mas_yr":-40.72,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":31.0945},"designations":[{"catalog":"HD","designation":"HD 176668"},{"catalog":"HIP","designation":"HIP 93053"},{"catalog":"HR","designation":"HR 7191"}],"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."}