{"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":"2026-08-27T17:05:44.024Z","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":"regulus","name":"Regulus","class":"b8ivn_blue_white_subgiant","category":"star","object_type":"B8IVn blue-white subgiant","mag":1.36,"mag_band":"V","abs_mag":-0.569,"abs_mag_band":"V","distance_ly":79.29905242702725,"distance_method":"parallax","ra_deg":152.09298,"dec_deg":11.967207,"epoch_ra_deg":152.450122,"epoch_dec_deg":11.836038,"epoch_moved_arcsec":6.649,"pm_ra_mas_yr":-249.4,"pm_dec_mas_yr":4.91,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Leo","discovered":"Antiquity","featured":true,"url":"https://spacecatalog.org/object/regulus","radius_km":null,"radius_kind":null,"data_quality":null,"description":"The heart of Leo, spinning near the speed at which it would tear itself apart, and paired with what is probably a stripped white dwarf.","properties":{"wds_id":"10084+1158","companions":[{"measured":2023,"magnitude":8.24,"components":"AB","discoverer_code":"STFB  6","separation_arcsec":175.9,"position_angle_deg":308},{"measured":2015,"magnitude":12.1,"components":"AD","discoverer_code":"HDO 127","separation_arcsec":195.3,"position_angle_deg":274}],"wikidata_id":"Q76493786","also_known_as":["Alpha Leonis","α Leo","α Leonis"],"spectral_type":"B8IVn","color_index_bv":-0.087,"luminosity_solar":147.09570767969763,"wikipedia_article":"Regulus","radial_velocity_km_s":6,"spectral_type_source":"SIMBAD (2024A&A...690A.176N, quality C)","proper_motion_ra_mas_yr":-249.4,"proper_motion_dec_mas_yr":4.91},"designations":[{"catalog":"Bayer/Flamsteed","designation":"32 Alpha Leo"},{"catalog":"Common name","designation":"Regulus"},{"catalog":"HD","designation":"HD 87901"},{"catalog":"HIP","designation":"HIP 49669"},{"catalog":"HR","designation":"HR 3982"}],"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."}