{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T05:10:51.364Z","years_from_j2000":26.669,"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-23609","name":"HD 23609","class":"f5_yellow_white_star","category":"star","object_type":"F5 yellow-white star","mag":6.98,"mag_band":"V","abs_mag":2.934,"abs_mag_band":"V","distance_ly":210.1523388542293,"distance_method":"parallax","ra_deg":56.821439999999996,"dec_deg":23.726751,"epoch_ra_deg":57.219831,"epoch_dec_deg":23.809861,"epoch_moved_arcsec":1.133,"pm_ra_mas_yr":-34.04,"pm_dec_mas_yr":-25.39,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Taurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-23609","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"03473+2344","age_years":2974166400,"companions":[{"measured":2016,"magnitude":12.7,"components":"AE","discoverer_code":"MCD   2","separation_arcsec":8,"position_angle_deg":42},{"measured":2015,"magnitude":12.57,"components":"AB","discoverer_code":"HL   19","separation_arcsec":66.4,"position_angle_deg":227},{"measured":2015,"magnitude":13.44,"components":"AD","discoverer_code":"HL   19","separation_arcsec":131,"position_angle_deg":244},{"measured":2015,"magnitude":12.35,"components":"AC","discoverer_code":"HL   19","separation_arcsec":147.6,"position_angle_deg":253}],"mass_solar":1.414,"radius_solar":2.15,"spectral_type":"F5","uncertainties":{"metallicity_fe_h":[0.17,0.17]},"color_index_bv":0.542,"luminosity_solar":5.839827246189301,"metallicity_fe_h":0.08,"radial_velocity_km_s":-8.9,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":3.867,"surface_temperature_k":6112,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":-34.04,"proper_motion_dec_mas_yr":-25.39,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":5.7067},"designations":[{"catalog":"HD","designation":"HD 23609"},{"catalog":"HIP","designation":"HIP 17684"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","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."}