{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.682","julian_year":2026.682,"time":"2026-09-07T02:59:35.206Z","years_from_j2000":26.682,"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-175531","name":"HD 175531","class":"g8_k0_v_yellow_main_sequence_star","category":"star","object_type":"G8/K0(V) yellow main-sequence star","mag":9.76,"mag_band":"V","abs_mag":5.716,"abs_mag_band":"V","distance_ly":210.0169839574768,"distance_method":"parallax","ra_deg":284.4861,"dec_deg":-44.968542,"epoch_ra_deg":284.975593,"epoch_dec_deg":-44.933267,"epoch_moved_arcsec":2.045,"pm_ra_mas_yr":25.08,"pm_dec_mas_yr":-72.42,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Corona Australis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-175531","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"18579-4458","companions":[{"measured":2025,"magnitude":12.71,"components":"AB","discoverer_code":"DON 936","separation_arcsec":1.5,"position_angle_deg":45}],"mass_solar":0.839,"radius_solar":0.938,"spectral_type":"G8/K0(V)","luminosity_solar":0.45040167816808707,"variable_mag_max":9.697,"variable_mag_min":9.807,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1978MSS...C02....0H, quality E)","surface_gravity_log_g":4.448,"surface_temperature_k":5272,"proper_motion_ra_mas_yr":25.08,"proper_motion_dec_mas_yr":-72.42,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":0.6065},"designations":[{"catalog":"HD","designation":"HD 175531"},{"catalog":"HIP","designation":"HIP 93096"}],"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."}