{"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":"2026-09-01T07:39:24.564Z","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-28271","name":"HD 28271","class":"f7v_yellow_white_main_sequence_star","category":"star","object_type":"F7V yellow-white main-sequence star","mag":6.38,"mag_band":"V","abs_mag":2.817,"abs_mag_band":"V","distance_ly":168.29538627632874,"distance_method":"parallax","ra_deg":67.21661999999999,"dec_deg":30.361492,"epoch_ra_deg":67.641219,"epoch_dec_deg":30.420848,"epoch_moved_arcsec":0.82,"pm_ra_mas_yr":23.05,"pm_dec_mas_yr":-20.33,"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-28271","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"04289+3022","companions":[{"measured":2020,"magnitude":8.03,"components":"AB","discoverer_code":"STF 548","separation_arcsec":14.9,"position_angle_deg":36},{"measured":2015,"magnitude":11.31,"components":"AC","discoverer_code":"STF 548","separation_arcsec":120.2,"position_angle_deg":197}],"spectral_type":"F7V","color_index_bv":0.547,"luminosity_solar":6.504291550788009,"metallicity_fe_h":-0.1,"variable_mag_max":6.344,"variable_mag_min":6.484,"radial_velocity_km_s":-37,"spectral_type_source":"SIMBAD (1990ApJ...354..310B, quality D)","surface_gravity_log_g":3.85,"surface_temperature_k":6238,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":23.05,"proper_motion_dec_mas_yr":-20.33,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 28271"},{"catalog":"HIP","designation":"HIP 20904"},{"catalog":"HR","designation":"HR 1406"}],"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."}