{"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":"2026-09-01T09:19:10.866Z","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-41997","name":"HD 41997","class":"o7_5vn_f_blue_main_sequence_star","category":"star","object_type":"O7.5Vn((f)) blue main-sequence star","mag":8.45,"mag_band":"V","abs_mag":-1.486,"abs_mag_band":"V","distance_ly":3166.5668182809,"distance_method":"parallax","ra_deg":92.232585,"dec_deg":15.705052,"epoch_ra_deg":92.618551,"epoch_dec_deg":15.700957,"epoch_moved_arcsec":0.316,"pm_ra_mas_yr":-3.32,"pm_dec_mas_yr":-11.39,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Orion","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-41997","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"radius_solar":12.092,"spectral_type":"O7.5Vn((f))","color_index_bv":0.351,"luminosity_solar":342.2945623160411,"radial_velocity_km_s":-18,"spectral_type_source":"SIMBAD (2011ApJS..193...24S, quality C)","surface_gravity_log_g":3.348,"surface_temperature_k":21019,"proper_motion_ra_mas_yr":-3.32,"proper_motion_dec_mas_yr":-11.39,"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 41997"},{"catalog":"HIP","designation":"HIP 29147"}],"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."}