Alpha Chamaeleontis

Alpha Chamaeleontis, Latinized from α Chamaeleontis, is a solitary^[10] star in the southern circumpolar constellation of Chamaeleon. It has an apparent visual magnitude of 4.06^[2] and thus is bright enough to be seen with the naked eye. With an annual parallax shift of 51.12 mas,^[1] it is located 63.8 light years from the Sun. The star is drifting closer with a radial velocity of −13 km/s,^[4] and is predicted to come to within 47 light-years in 666,000 years.^[5]

α Chamaeleontis

Location of α Chamaeleontis (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Chamaeleon
Right ascension	08h 18m 31.55319s[1]
Declination	−76° 55′ 10.9964″[1]
Apparent magnitude (V)	4.06[2]
Characteristics
Spectral type	F5 V Fe-0.8[3]
U−B color index	−0.04[2]
B−V color index	+0.40[2]
Astrometry
Radial velocity (Rv)	−13.4±0.5[4] km/s
Proper motion (μ)	RA: 111.12[1] mas/yr Dec.: 107.49[1] mas/yr
Parallax (π)	51.12±0.12 mas[1]
Distance	63.8 ± 0.1 ly (19.56 ± 0.05 pc)
Absolute magnitude (MV)	+2.59[5]
Details
Mass	1.42[6] M☉
Radius	2.11+0.14 −0.05[7] R☉
Luminosity	7.542±0.062[7] L☉
Surface gravity (log g)	4.28±0.14[6] cgs
Temperature	6,580+91 −209[7] K
Metallicity [Fe/H]	−0.26[3] dex
Rotational velocity (v sin i)	0[8] km/s
Age	1.8[6] Gyr
Other designations
α Cha, Alpha Cha, CPD−76°507, GJ 305, HD 71243, HIP 40702, HR 3318, SAO 256496[9]
Database references
SIMBAD	data

This is an F-type main sequence star with a stellar classification of F5 V Fe−0.8,^[3] where the 'Fe−0.8' notation indicates an anomalously low abundance of iron. It has an estimated 1.4 times the mass of the Sun,^[6] 2.1 times the Sun's radius,^[7] and radiates 7.5 times the solar luminosity from its outer atmosphere at an effective temperature of 6,580 K.^[7] The star is around 1.8^[6] billion years old with a projected rotational velocity that is too low to be measured.^[8] The star has been examined for an infrared excess that would suggest the presence of an orbiting debris disk, but none was found.^[11]