54 Leonis
Star in the constellation Leo
54 Leonis is a binary star system in the zodiac constellation of Leo, located around 321 light years from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 4.30. As of 2017, the pair had an angular separation of 6.60″ along a position angle of 113°. They have a physical separation of around 533 AU (79,700 Gm).
The magnitude 4.477 primary, designated component A, is an A-type main-sequence star with a stellar classification of A0 V, which indicates it is generating energy through hydrogen fusion at its core. It has a high rate of spin, showing a projected rotational velocity of 185 km/s. This is giving the star an oblate shape with an equatorial bulge that is an estimated 8% larger than the polar radius. The star is roughly 411 million years old with 2.4 times the mass of the Sun and about 4.9 times the Sun's radius.
The fainter magnitude 6.29 secondary, component B, is a smaller A-type main-sequence star with a class of A2 Vn. The 'n' suffix indicates wide "nebulous" lines due to rapid rotation.
The public source identifies “54 Leonis” as star in the constellation Leo. This brief keeps that definition visible, then builds a research path around Leonis, Star and constellation.
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This entry incorporates text from “54 Leonis” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.