{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T21:19:12.695Z","years_from_j2000":26.681,"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-216172","name":"HD 216172","class":"f4v_f5v_yellow_white_main_sequence_star","category":"star","object_type":"F4V+F5V yellow-white main-sequence star","mag":6.19,"mag_band":"V","abs_mag":2.169,"abs_mag_band":"V","distance_ly":207.7430216920357,"distance_method":"parallax","ra_deg":342.253125,"dec_deg":68.570228,"epoch_ra_deg":342.47828,"epoch_dec_deg":68.712572,"epoch_moved_arcsec":3.609,"pm_ra_mas_yr":117.3,"pm_dec_mas_yr":67.39,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cepheus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-216172","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"22490+6834","age_years":2160594700,"companions":[{"measured":2021,"magnitude":7.02,"components":"AB","discoverer_code":"STF2947","separation_arcsec":4.7,"position_angle_deg":55},{"measured":2015,"magnitude":12.48,"components":"AC","discoverer_code":"STF2947","separation_arcsec":122.6,"position_angle_deg":208}],"mass_solar":1.41,"radius_solar":1.777,"spectral_type":"F4V+F5V","uncertainties":{"metallicity_fe_h":[0.017,0.017]},"color_index_bv":0.44,"luminosity_solar":11.81408251920887,"metallicity_fe_h":0.49,"radial_velocity_km_s":3,"spectral_type_source":"SIMBAD (1935ApJ....81..187A, quality D)","surface_gravity_log_g":4.049,"surface_temperature_k":6593,"metallicity_fe_h_source":"Median of 3 spectroscopic determinations in 3 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":117.3,"proper_motion_dec_mas_yr":67.39,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":5.3093},"designations":[{"catalog":"HD","designation":"HD 216172"},{"catalog":"HIP","designation":"HIP 112670"},{"catalog":"HR","designation":"HR 8687"}],"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."}