{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.654","julian_year":2026.654,"time":"2026-08-27T17:05:52.575Z","years_from_j2000":26.654,"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-2884","name":"β¹ Tuc","class":"b9_5va_blue_white_main_sequence_star","category":"star","object_type":"B9.5Va blue-white main-sequence star","mag":4.36,"mag_band":"V","abs_mag":1.275,"abs_mag_band":"V","distance_ly":135.0545067285714,"distance_method":"parallax","ra_deg":7.885875,"dec_deg":-62.958218,"epoch_ra_deg":8.194807,"epoch_dec_deg":-62.810323,"epoch_moved_arcsec":2.633,"pm_ra_mas_yr":82.48,"pm_dec_mas_yr":-54.37,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Tucana","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-2884","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"00315-6257","companions":[{"measured":1932,"magnitude":13.5,"components":"AB","discoverer_code":"B     7","separation_arcsec":2.6,"position_angle_deg":153},{"measured":2021,"magnitude":4.51,"components":"AC","discoverer_code":"LCL 119","separation_arcsec":27.1,"position_angle_deg":168},{"measured":2000,"magnitude":5.07,"components":"AE","discoverer_code":"SHY 114","separation_arcsec":548.9,"position_angle_deg":118}],"mass_solar":2.477,"radius_solar":1.899,"spectral_type":"B9.5Va","color_index_bv":-0.064,"luminosity_solar":26.915348039269155,"radial_velocity_km_s":14,"spectral_type_source":"SIMBAD (2017AJ....154...31G, quality B)","surface_gravity_log_g":4.263,"surface_temperature_k":10567,"proper_motion_ra_mas_yr":82.48,"proper_motion_dec_mas_yr":-54.37,"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","bolometric_luminosity_solar":41.5082},"designations":[{"catalog":"Bayer/Flamsteed","designation":"Beta1 Tuc"},{"catalog":"HD","designation":"HD 2884"},{"catalog":"HIP","designation":"HIP 2484"},{"catalog":"HR","designation":"HR 126"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-27T16:03:54.983Z","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."}