{"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":"2026-08-31T16:42:54.572Z","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-5901","name":"HD 5901","class":"f3iii_yellow_white_giant","category":"star","object_type":"F3III yellow-white giant","mag":8.36,"mag_band":"V","abs_mag":1.824,"abs_mag_band":"V","distance_ly":661.574944247887,"distance_method":"parallax","ra_deg":15.173910000000001,"dec_deg":9.486874,"epoch_ra_deg":15.524219,"epoch_dec_deg":9.631601,"epoch_moved_arcsec":0.196,"pm_ra_mas_yr":7.17,"pm_dec_mas_yr":-1.63,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Pisces","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-5901","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"01007+0929","age_years":835146960,"companions":[{"measured":2018,"magnitude":9.71,"components":"AB","discoverer_code":"STF  82","separation_arcsec":1.9,"position_angle_deg":304},{"measured":2017,"magnitude":11.87,"components":"AC","discoverer_code":"DOO  25","separation_arcsec":74.5,"position_angle_deg":214}],"mass_solar":2.213,"radius_solar":4.441,"spectral_type":"F3III","color_index_bv":0.427,"luminosity_solar":16.23304527765459,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (2020AJ....160...52M, quality C)","surface_gravity_log_g":3.393,"surface_temperature_k":6618,"proper_motion_ra_mas_yr":7.17,"proper_motion_dec_mas_yr":-1.63,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":35.3559},"designations":[{"catalog":"HD","designation":"HD 5901"},{"catalog":"HIP","designation":"HIP 4728"}],"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."}