{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.677","julian_year":2026.677,"time":"2026-09-05T04:00:55.188Z","years_from_j2000":26.677,"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-164575","name":"HD 164575","class":"k0_orange_star","category":"star","object_type":"K0 orange star","mag":6.71,"mag_band":"V","abs_mag":1.578,"abs_mag_band":"V","distance_ly":346.60605644320555,"distance_method":"parallax","ra_deg":269.90367,"dec_deg":43.235377,"epoch_ra_deg":270.107158,"epoch_dec_deg":43.233662,"epoch_moved_arcsec":2.02,"pm_ra_mas_yr":-5.9,"pm_dec_mas_yr":75.5,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Hercules","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-164575","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"17596+4314","age_years":5471833700,"companions":[{"measured":2016,"magnitude":10,"components":null,"discoverer_code":"COU1784","separation_arcsec":2.2,"position_angle_deg":97}],"mass_solar":1.243,"radius_solar":9.093,"spectral_type":"K0","uncertainties":{"metallicity_fe_h":[0.015,0.015]},"color_index_bv":1.106,"luminosity_solar":20.361042011319697,"metallicity_fe_h":-0.115,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":2.494,"surface_temperature_k":4574,"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":-5.9,"proper_motion_dec_mas_yr":75.5,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":32.3795},"designations":[{"catalog":"HD","designation":"HD 164575"},{"catalog":"HIP","designation":"HIP 88103"}],"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."}