Beta Caeli
Beta Caeli is a star with an orbiting companion in the southern constellation of Caelum. Its name is a Bayer designation that is Latinized from β Caeli, and abbreviated Beta Cae or β Cae. This star is dimly visible to the naked eye, having an apparent visual magnitude of 5.04. Based upon an annual parallax shift of as seen from Earth, it is located at a distance of. The star is moving away from the Sun with a radial velocity of +27.5 km/s.
Characteristics
Beta Caeli is a probable single-lined spectroscopic binary system, meaning only the spectral lines of the visible component can be seen. This primary component has a stellar classification of F3 V or F3 IV, indicating it is either an F-type main-sequence star or a somewhat more evolved subgiant star, respectively. It has an estimated 1.5 times the mass of the Sun and about 1.9 times the Sun's radius. The star is 200 million to two billion years old and has a high rate of spin with a projected rotational velocity of around 97.5 km/s. It is radiating 6.6 times the luminosity of the Sun from its photosphere at an effective temperature of 6,666 K. Based on the amount of iron detected, the abundance of elements with mass greater than helium is lower than in the Sun.The low-mass companion is orbiting about from the primary, with an orbital period of around seven years. Its exact mass is uncertain; an orbital solution suggest it is close to the brown dwarf regime at around, but models of stellar atmospheres suggest a higher mass of. It was first detected in 2017 and was believed to be either a brown dwarf or a star with minimum mass around. In 2022, Beta Caeli was imaged with the Gemini Planet Imager, with a point source that very likely is being detected. This object may be the source of the X-ray emission coming from the same location, which suggests the companion could be a late-type star.
The existence of additional companions beyond 55 astronomical units is ruled out.