{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.664","julian_year":2026.664,"time":"2026-08-31T13:31:48.734Z","years_from_j2000":26.664,"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-45901","name":"HD 45901","class":"b0_1ve_blue_white_main_sequence_star","category":"star","object_type":"B0-1Ve blue-white main-sequence star","mag":8.85,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":97.573455,"dec_deg":2.847892,"epoch_ra_deg":97.924786,"epoch_dec_deg":2.83003,"epoch_moved_arcsec":0.045,"pm_ra_mas_yr":0.44,"pm_dec_mas_yr":-1.64,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Monoceros","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-45901","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"radius_solar":6.693,"spectral_type":"B0-1Ve","color_index_bv":0.309,"variable_mag_max":8.79,"variable_mag_min":8.93,"radial_velocity_km_s":12,"spectral_type_source":"SIMBAD (2011BASI...39..517M, quality C)","surface_gravity_log_g":4.002,"surface_temperature_k":33082,"proper_motion_ra_mas_yr":0.44,"proper_motion_dec_mas_yr":-1.64,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate"},"designations":[{"catalog":"HD","designation":"HD 45901"},{"catalog":"HIP","designation":"HIP 30992"}],"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."}