Xi Octantis, Latinized from ξ Octantis, is a solitary variable star in the southern circumpolar constellation Octans. It has an apparent magnitude of about 5.3, allowing it to be faintly seen with the naked eye; however, this varies slightly. Located 514 light years away, the object is receding with a heliocentric radial velocity of 22 km/s.
Xi Octantis has a stellar classification of B6 V, indicating that it is an ordinary B-type main-sequence star. Hintler et al. gives it a luminosity class IV (subgiant) while Houk and Cowley gives a classification intermediate between a B5 and B7 dwarf. Nevertheless, it has 4 times the mass of the Sun and is 3 times larger. It shines with a luminosity of 360 L☉ from its photosphere at an effective temperature of 14,050 K, giving it a whitish blue glow. Xi Octantis is 46 million years old – 64.8% through its short main sequence lifetime – and spins modestly with a projected rotational velocity of 30 km/s.
When the Hipparcos catalogue was released in 1997, Xi Octantis was found to vary in magnitude — ranging from 5.32 to 5.36 based on data from the International Variable Star Index. It has since been classified as a Slowly pulsating B-dwarf with a period of 1.78 days.
References
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