{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-02T02:02:26.763Z","years_from_j2000":26.668,"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-38475","name":"HD 38475","class":"a_g_white_star","category":"star","object_type":"A/G white star","mag":6.61,"mag_band":"V","abs_mag":-3.347,"abs_mag_band":"V","distance_ly":3197.6116869374905,"distance_method":"parallax","ra_deg":87.75457499999999,"dec_deg":65.754069,"epoch_ra_deg":88.430078,"epoch_dec_deg":65.761384,"epoch_moved_arcsec":0.148,"pm_ra_mas_yr":-3.72,"pm_dec_mas_yr":4.1,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Camelopardalis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-38475","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"05511+6545","companions":[{"measured":2019,"magnitude":8.23,"components":"AB","discoverer_code":"STF 780","separation_arcsec":4,"position_angle_deg":105},{"measured":2019,"magnitude":10.18,"components":"AC","discoverer_code":"STF 780","separation_arcsec":12.5,"position_angle_deg":148},{"measured":2015,"magnitude":13.8,"components":"AD","discoverer_code":"STF 780","separation_arcsec":18.8,"position_angle_deg":59}],"mass_solar":3.893,"radius_solar":22.68,"spectral_type":"A/G","color_index_bv":0.822,"luminosity_solar":1900.2030025772322,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (2020AJ....160...52M, quality E)","surface_gravity_log_g":2.279,"surface_temperature_k":5285,"proper_motion_ra_mas_yr":-3.72,"proper_motion_dec_mas_yr":4.1,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":340.7968},"designations":[{"catalog":"HD","designation":"HD 38475"},{"catalog":"HIP","designation":"HIP 27634"}],"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."}