{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.666","julian_year":2026.666,"time":"2026-09-01T05:29:19.672Z","years_from_j2000":26.666,"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-43812","name":"4 Lyn","class":"a2vp_white_main_sequence_star","category":"star","object_type":"A2Vp white main-sequence star","mag":6.05,"mag_band":"V","abs_mag":0.138,"abs_mag_band":"V","distance_ly":496.43283783132364,"distance_method":"parallax","ra_deg":95.51481,"dec_deg":59.372099,"epoch_ra_deg":96.110184,"epoch_dec_deg":59.359273,"epoch_moved_arcsec":0.149,"pm_ra_mas_yr":-5.55,"pm_dec_mas_yr":0.6,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Lynx","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-43812","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"06221+5922","companions":[{"measured":1986,"magnitude":7.38,"components":"Aa,Ab","discoverer_code":"CHR 128","separation_arcsec":0.2,"position_angle_deg":110},{"measured":2023,"magnitude":7.52,"components":"AB","discoverer_code":"STF 881","separation_arcsec":0.7,"position_angle_deg":154},{"measured":2022,"magnitude":12.3,"components":"AC","discoverer_code":"STF 881","separation_arcsec":26.7,"position_angle_deg":98},{"measured":2016,"magnitude":12.2,"components":"AB,E","discoverer_code":"WAL  45","separation_arcsec":74.9,"position_angle_deg":32},{"measured":2022,"magnitude":11.89,"components":"AD","discoverer_code":"STF 881","separation_arcsec":100.4,"position_angle_deg":357}],"spectral_type":"A2Vp","color_index_bv":0.153,"luminosity_solar":76.70081876935099,"radial_velocity_km_s":-24,"spectral_type_source":"SIMBAD (1995ApJS...99..135A, quality C)","surface_temperature_k":9462,"proper_motion_ra_mas_yr":-5.55,"proper_motion_dec_mas_yr":0.6,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"4 Lyn"},{"catalog":"HD","designation":"HD 43812"},{"catalog":"HIP","designation":"HIP 30272"},{"catalog":"HR","designation":"HR 2257"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}