X Caeli
X Caeli is a binary star system in the southern constellation of Caelum. It has the Bayer designation Gamma2 Caeli, which is Latinized from γ2 Caeli and abbreviated Gamma2 Cae or γ2 Cae; X Caeli is the system's variable star designation. This system is barely visible to the naked eye with a combined apparent [visual magnitude] of 6.32. Based upon an annual parallax shift of, it is located at a distance of from Earth. The system is moving further away from the Sun with a radial velocity of +6 km/s.
Properties
The yellow-white-hued primary, component A, has an apparent magnitude of +6.32 and stellar classification of F2 IV/V, showing mixed traits of an F-type main-sequence star and a subgiant. The spectral lines display a narrow absorption core that suggests the presence of a circumstellar shell.This star is classified as a Delta [Scuti variable] with a brightness varies from magnitude over a period of 3.25 hours. A 2000 observing campaign identified at least six independent pulsation modes for this variation. It has 1.5 times the mass of the Sun and 3.4 times the Sun's radius. This star is radiating 24 times the luminosity of the Sun from its photosphere at an effective temperature of 7,227 K. It is nearly a billion years old, with a relatively high rate of rotation, showing a projected rotational velocity of 69 km/s.
The companion star, component B, has an apparent magnitude of +9.65 and, as of 2000, is at an angular separation of along a position angle of 183°. The orbital period for this binary star system is unknown.