{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.676","julian_year":2026.676,"time":"2026-09-04T19:07:20.517Z","years_from_j2000":26.676,"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-27638","name":"59 χ Tau","class":"b9vnn_blue_white_main_sequence_star","category":"star","object_type":"B9Vnn blue-white main-sequence star","mag":5.38,"mag_band":"V","abs_mag":0.626,"abs_mag_band":"V","distance_ly":291.2110049390384,"distance_method":"parallax","ra_deg":65.645595,"dec_deg":25.629314,"epoch_ra_deg":66.054972,"epoch_dec_deg":25.692441,"epoch_moved_arcsec":0.723,"pm_ra_mas_yr":20.37,"pm_dec_mas_yr":-17.88,"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-27638","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"04226+2538","companions":[{"measured":2016,"magnitude":8.54,"components":"AB","discoverer_code":"STF 528","separation_arcsec":19.4,"position_angle_deg":25}],"spectral_type":"B9Vnn","color_index_bv":-0.041,"luminosity_solar":48.932792408193684,"radial_velocity_km_s":17,"spectral_type_source":"SIMBAD (1983ApJ...272..182A, quality C)","surface_temperature_k":10280,"proper_motion_ra_mas_yr":20.37,"proper_motion_dec_mas_yr":-17.88,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"59 Chi Tau"},{"catalog":"HD","designation":"HD 27638"},{"catalog":"HIP","designation":"HIP 20430"},{"catalog":"HR","designation":"HR 1369"}],"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."}